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Question 99: The Finite Expansion Includes Every k from Zero through n

On this page
  1. Original question and givens
  2. Definition and scope
  3. Step-by-step derivation
  4. Reverse checks
  5. Result
  6. This question review and source binding

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P250-0099 · q-20261014-advance-20261109-r05-binomial-theorem-0049

Original question and givens

Use natural exponent n=23, including0, in a commutative coefficient setting. Give (n, coefficient_exponent_rows, boundary).

  • G001 — Use natural exponent n=23, including0, in a commutative coefficient setting. Give (n, coefficient_exponent_rows, boundary).

Definition and scope

n is a nonnegative integer and x,y commute. For n=0 use the polynomial empty-product identity.

Step-by-step derivation

S001 · implies

Before

n=23≥0; x,y commute

After

(x+y)^23 is a finite product of 23 factors

Conditions: none

Choose x or y from each factor; commutativity permits grouping products by the number of y choices.

Step identifiers and dependencies

Rule: finite_product · Uses: G001

S002 · implies

Before

choose exactly 0 of 23 factors to contribute y

After

C(23,0)=25852016738884976640000/(1·25852016738884976640000)=1

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 0 y positions and 23 x positions, giving coefficient 1.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S001

S003 · implies

Before

C(23,0)=1; choose y 0 times

After

1·x^23·y^0

Conditions: none

The x exponent is 23-0=23; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S002

S004 · implies

Before

choose exactly 1 of 23 factors to contribute y

After

C(23,1)=25852016738884976640000/(1·1124000727777607680000)=23

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 1 y positions and 22 x positions, giving coefficient 23.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S003

S005 · implies

Before

C(23,1)=23; choose y 1 times

After

23·x^22·y^1

Conditions: none

The x exponent is 23-1=22; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S004

S006 · implies

Before

choose exactly 2 of 23 factors to contribute y

After

C(23,2)=25852016738884976640000/(2·51090942171709440000)=253

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 2 y positions and 21 x positions, giving coefficient 253.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S005

S007 · implies

Before

C(23,2)=253; choose y 2 times

After

253·x^21·y^2

Conditions: none

The x exponent is 23-2=21; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S006

S008 · implies

Before

choose exactly 3 of 23 factors to contribute y

After

C(23,3)=25852016738884976640000/(6·2432902008176640000)=1771

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 3 y positions and 20 x positions, giving coefficient 1771.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S007

S009 · implies

Before

C(23,3)=1771; choose y 3 times

After

1771·x^20·y^3

Conditions: none

The x exponent is 23-3=20; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S008

S010 · implies

Before

choose exactly 4 of 23 factors to contribute y

After

C(23,4)=25852016738884976640000/(24·121645100408832000)=8855

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 4 y positions and 19 x positions, giving coefficient 8855.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S009

S011 · implies

Before

C(23,4)=8855; choose y 4 times

After

8855·x^19·y^4

Conditions: none

The x exponent is 23-4=19; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S010

S012 · implies

Before

choose exactly 5 of 23 factors to contribute y

After

C(23,5)=25852016738884976640000/(120·6402373705728000)=33649

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 5 y positions and 18 x positions, giving coefficient 33649.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S011

S013 · implies

Before

C(23,5)=33649; choose y 5 times

After

33649·x^18·y^5

Conditions: none

The x exponent is 23-5=18; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S012

S014 · implies

Before

choose exactly 6 of 23 factors to contribute y

After

C(23,6)=25852016738884976640000/(720·355687428096000)=100947

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 6 y positions and 17 x positions, giving coefficient 100947.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S013

S015 · implies

Before

C(23,6)=100947; choose y 6 times

After

100947·x^17·y^6

Conditions: none

The x exponent is 23-6=17; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S014

S016 · implies

Before

choose exactly 7 of 23 factors to contribute y

After

C(23,7)=25852016738884976640000/(5040·20922789888000)=245157

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 7 y positions and 16 x positions, giving coefficient 245157.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S015

S017 · implies

Before

C(23,7)=245157; choose y 7 times

After

245157·x^16·y^7

Conditions: none

The x exponent is 23-7=16; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S016

S018 · implies

Before

choose exactly 8 of 23 factors to contribute y

After

C(23,8)=25852016738884976640000/(40320·1307674368000)=490314

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 8 y positions and 15 x positions, giving coefficient 490314.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S017

S019 · implies

Before

C(23,8)=490314; choose y 8 times

After

490314·x^15·y^8

Conditions: none

The x exponent is 23-8=15; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S018

S020 · implies

Before

choose exactly 9 of 23 factors to contribute y

After

C(23,9)=25852016738884976640000/(362880·87178291200)=817190

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 9 y positions and 14 x positions, giving coefficient 817190.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S019

S021 · implies

Before

C(23,9)=817190; choose y 9 times

After

817190·x^14·y^9

Conditions: none

The x exponent is 23-9=14; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S020

S022 · implies

Before

choose exactly 10 of 23 factors to contribute y

After

C(23,10)=25852016738884976640000/(3628800·6227020800)=1144066

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 10 y positions and 13 x positions, giving coefficient 1144066.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S021

S023 · implies

Before

C(23,10)=1144066; choose y 10 times

After

1144066·x^13·y^10

Conditions: none

The x exponent is 23-10=13; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S022

S024 · implies

Before

choose exactly 11 of 23 factors to contribute y

After

C(23,11)=25852016738884976640000/(39916800·479001600)=1352078

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 11 y positions and 12 x positions, giving coefficient 1352078.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S023

S025 · implies

Before

C(23,11)=1352078; choose y 11 times

After

1352078·x^12·y^11

Conditions: none

The x exponent is 23-11=12; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S024

S026 · implies

Before

choose exactly 12 of 23 factors to contribute y

After

C(23,12)=25852016738884976640000/(479001600·39916800)=1352078

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 12 y positions and 11 x positions, giving coefficient 1352078.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S025

S027 · implies

Before

C(23,12)=1352078; choose y 12 times

After

1352078·x^11·y^12

Conditions: none

The x exponent is 23-12=11; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S026

S028 · implies

Before

choose exactly 13 of 23 factors to contribute y

After

C(23,13)=25852016738884976640000/(6227020800·3628800)=1144066

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 13 y positions and 10 x positions, giving coefficient 1144066.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S027

S029 · implies

Before

C(23,13)=1144066; choose y 13 times

After

1144066·x^10·y^13

Conditions: none

The x exponent is 23-13=10; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S028

S030 · implies

Before

choose exactly 14 of 23 factors to contribute y

After

C(23,14)=25852016738884976640000/(87178291200·362880)=817190

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 14 y positions and 9 x positions, giving coefficient 817190.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S029

S031 · implies

Before

C(23,14)=817190; choose y 14 times

After

817190·x^9·y^14

Conditions: none

The x exponent is 23-14=9; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S030

S032 · implies

Before

choose exactly 15 of 23 factors to contribute y

After

C(23,15)=25852016738884976640000/(1307674368000·40320)=490314

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 15 y positions and 8 x positions, giving coefficient 490314.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S031

S033 · implies

Before

C(23,15)=490314; choose y 15 times

After

490314·x^8·y^15

Conditions: none

The x exponent is 23-15=8; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S032

S034 · implies

Before

choose exactly 16 of 23 factors to contribute y

After

C(23,16)=25852016738884976640000/(20922789888000·5040)=245157

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 16 y positions and 7 x positions, giving coefficient 245157.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S033

S035 · implies

Before

C(23,16)=245157; choose y 16 times

After

245157·x^7·y^16

Conditions: none

The x exponent is 23-16=7; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S034

S036 · implies

Before

choose exactly 17 of 23 factors to contribute y

After

C(23,17)=25852016738884976640000/(355687428096000·720)=100947

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 17 y positions and 6 x positions, giving coefficient 100947.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S035

S037 · implies

Before

C(23,17)=100947; choose y 17 times

After

100947·x^6·y^17

Conditions: none

The x exponent is 23-17=6; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S036

S038 · implies

Before

choose exactly 18 of 23 factors to contribute y

After

C(23,18)=25852016738884976640000/(6402373705728000·120)=33649

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 18 y positions and 5 x positions, giving coefficient 33649.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S037

S039 · implies

Before

C(23,18)=33649; choose y 18 times

After

33649·x^5·y^18

Conditions: none

The x exponent is 23-18=5; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S038

S040 · implies

Before

choose exactly 19 of 23 factors to contribute y

After

C(23,19)=25852016738884976640000/(121645100408832000·24)=8855

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 19 y positions and 4 x positions, giving coefficient 8855.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S039

S041 · implies

Before

C(23,19)=8855; choose y 19 times

After

8855·x^4·y^19

Conditions: none

The x exponent is 23-19=4; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S040

S042 · implies

Before

choose exactly 20 of 23 factors to contribute y

After

C(23,20)=25852016738884976640000/(2432902008176640000·6)=1771

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 20 y positions and 3 x positions, giving coefficient 1771.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S041

S043 · implies

Before

C(23,20)=1771; choose y 20 times

After

1771·x^3·y^20

Conditions: none

The x exponent is 23-20=3; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S042

S044 · implies

Before

choose exactly 21 of 23 factors to contribute y

After

C(23,21)=25852016738884976640000/(51090942171709440000·2)=253

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 21 y positions and 2 x positions, giving coefficient 253.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S043

S045 · implies

Before

C(23,21)=253; choose y 21 times

After

253·x^2·y^21

Conditions: none

The x exponent is 23-21=2; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S044

S046 · implies

Before

choose exactly 22 of 23 factors to contribute y

After

C(23,22)=25852016738884976640000/(1124000727777607680000·1)=23

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 22 y positions and 1 x positions, giving coefficient 23.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S045

S047 · implies

Before

C(23,22)=23; choose y 22 times

After

23·x^1·y^22

Conditions: none

The x exponent is 23-22=1; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S046

S048 · implies

Before

choose exactly 23 of 23 factors to contribute y

After

C(23,23)=25852016738884976640000/(25852016738884976640000·1)=1

Conditions: none

Count orderings of 23 positions and divide by reorderings within the 23 y positions and 0 x positions, giving coefficient 1.

Step identifiers and dependencies

Rule: subset_count · Uses: G001, S047

S049 · implies

Before

C(23,23)=1; choose y 23 times

After

1·x^0·y^23

Conditions: none

The x exponent is 23-23=0; the two exponents still sum to 23.

Step identifiers and dependencies

Rule: group_like_terms · Uses: G001, S048

S050 · implies

Before

all k=0 through 23 have been accounted for

After

(x+y)^23=1·x^23·y^0 + 23·x^22·y^1 + 253·x^21·y^2 + 1771·x^20·y^3 + 8855·x^19·y^4 + 33649·x^18·y^5 + 100947·x^17·y^6 + 245157·x^16·y^7 + 490314·x^15·y^8 + 817190·x^14·y^9 + 1144066·x^13·y^10 + 1352078·x^12·y^11 + 1352078·x^11·y^12 + 1144066·x^10·y^13 + 817190·x^9·y^14 + 490314·x^8·y^15 + 245157·x^7·y^16 + 100947·x^6·y^17 + 33649·x^5·y^18 + 8855·x^4·y^19 + 1771·x^3·y^20 + 253·x^2·y^21 + 23·x^1·y^22 + 1·x^0·y^23

Conditions: none

Every x/y choice belongs to exactly one k class, so this is the complete finite expansion, not just endpoint terms.

Step identifiers and dependencies

Rule: collect_all_terms · Uses: G001, S049

Reverse checks

  • S050 · premise_and_result_audit — There are n+1 coefficient positions, with the complete range of k retained.
  • S049 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S048 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S047 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S046 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S045 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S044 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S043 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S042 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S041 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S040 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S039 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S038 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S037 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S036 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S035 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S034 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S033 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S032 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S031 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S030 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S029 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S028 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S027 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S026 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S025 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S024 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S023 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S022 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S021 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S020 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S019 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S018 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S017 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S016 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S015 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S014 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S013 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S012 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S011 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S010 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S009 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S008 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S007 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S006 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S005 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S004 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S003 · premise_and_result_audit — The answer row is [k,coefficient,x exponent,y exponent]; do not swap the exponent columns.
  • S002 · premise_and_result_audit — Check the coefficient independently with the integer Pascal recurrence, not approximate factorials.
  • S001 · premise_and_result_audit — This is not an infinite expansion for a noninteger power or a claim for noncommuting multiplication.

Result

(23, [[0, 1, 23, 0], [1, 23, 22, 1], [2, 253, 21, 2], [3, 1771, 20, 3], [4, 8855, 19, 4], [5, 33649, 18, 5], [6, 100947, 17, 6], [7, 245157, 16, 7], [8, 490314, 15, 8], [9, 817190, 14, 9], [10, 1144066, 13, 10], [11, 1352078, 12, 11], [12, 1352078, 11, 12], [13, 1144066, 10, 13], [14, 817190, 9, 14], [15, 490314, 8, 15], [16, 245157, 7, 16], [17, 100947, 6, 17], [18, 33649, 5, 18], [19, 8855, 4, 19], [20, 1771, 3, 20], [21, 253, 2, 21], [22, 23, 1, 22], [23, 1, 0, 23]], complete_k_zero_through_n_coefficients)

The full expansion consists of all displayed monomials, in the same order as the answer rows.

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Review date: 2026-10-24

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