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Question 962: Order Divides Phi without Automatically Equaling Phi

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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P1000-0962 · q-20261015-advance-20261116-r07-multiplicative-order-mod-n-0062

Original question and givens

Use exact modulus n=14 and integer a=3. First require n≥2 and normalize a modulo n into the canonical nonnegative residue, then require gcd(a,n)=1. The order is the least positive return exponent, not any return. Give (order, phi, order_divides_phi, power_rows, certificate).

  • G001 — Use exact modulus n=14 and integer a=3. First require n≥2 and normalize a modulo n into the canonical nonnegative residue, then require gcd(a,n)=1. The order is the least positive return exponent, not any return. Give (order, phi, order_divides_phi, power_rows, certificate).

Definition and scope

The units split into equal-length orbits, so the order divides phi(n); neither equality nor a primitive root follows.

Step-by-step derivation

S001 · implies

Before

n=14; a=3

After

order is defined here only for n≥2 and units modulo n

Conditions: none

Fix this node's domain first; do not confuse additive and multiplicative order.

Step identifiers and dependencies

Rule: order_domain · Uses: G001

S002 · implies

Before

a=3

After

normalized residue=3; gcd(3,14)=1

Conditions: none

Normalize even a negative representative into[0,n), then test coprimality.

Step identifiers and dependencies

Rule: normalize_and_qualify · Uses: G001, S001

S003 · implies

Before

gcd(residue,n)=1; units=[1, 3, 5, 9, 11, 13]

After

phi(14)=6

Conditions: none

Enumerate every coprime class from0 through n−1; phi is the complete unit-carrier size.

Step identifiers and dependencies

Rule: complete_unit_enumeration · Uses: G001, S002

S004 · calculation

Before

power product at k=1 := mul(1, 3)

After

power product at k=1 = 3

Conditions: none

Multiply the preceding power representative by the same normalized base.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S003

S005 · implies

Before

product=3

After

a^1 mod 14=3

Conditions: none

The remainder is the next full power representative.

Step identifiers and dependencies

Rule: reduce_next_power · Uses: G001, S004

S006 · calculation

Before

power product at k=2 := mul(3, 3)

After

power product at k=2 = 9

Conditions: none

Multiply the preceding power representative by the same normalized base.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S005

S007 · implies

Before

product=9

After

a^2 mod 14=9

Conditions: none

The remainder is the next full power representative.

Step identifiers and dependencies

Rule: reduce_next_power · Uses: G001, S006

S008 · calculation

Before

power product at k=3 := mul(9, 3)

After

power product at k=3 = 27

Conditions: none

Multiply the preceding power representative by the same normalized base.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S007

S009 · implies

Before

product=27

After

a^3 mod 14=13

Conditions: none

The remainder is the next full power representative.

Step identifiers and dependencies

Rule: reduce_next_power · Uses: G001, S008

S010 · calculation

Before

power product at k=4 := mul(13, 3)

After

power product at k=4 = 39

Conditions: none

Multiply the preceding power representative by the same normalized base.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S009

S011 · implies

Before

product=39

After

a^4 mod 14=11

Conditions: none

The remainder is the next full power representative.

Step identifiers and dependencies

Rule: reduce_next_power · Uses: G001, S010

S012 · calculation

Before

power product at k=5 := mul(11, 3)

After

power product at k=5 = 33

Conditions: none

Multiply the preceding power representative by the same normalized base.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S011

S013 · implies

Before

product=33

After

a^5 mod 14=5

Conditions: none

The remainder is the next full power representative.

Step identifiers and dependencies

Rule: reduce_next_power · Uses: G001, S012

S014 · calculation

Before

power product at k=6 := mul(5, 3)

After

power product at k=6 = 15

Conditions: none

Multiply the preceding power representative by the same normalized base.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S013

S015 · implies

Before

product=15

After

a^6 mod 14=1

Conditions: none

The remainder is the next full power representative.

Step identifiers and dependencies

Rule: reduce_next_power · Uses: G001, S014

S016 · implies

Before

all positive k<=6: [[1, 3], [2, 9], [3, 13], [4, 11], [5, 5], [6, 1]]

After

first positive return to1 occurs at k=6

Conditions: none

Every smaller positive exponent has been checked not to return to1; the identity at exponent0 is not the order.

Step identifiers and dependencies

Rule: least_positive_return · Uses: G001, S015

S017 · implies

Before

multiply unit 1 successively by 3

After

orbit=[1, 3, 9, 13, 11, 5]; length=6

Conditions: none

Multiplication by a unit is bijective; an earlier return would cancel the starting unit and contradict the least positive order.

Step identifiers and dependencies

Rule: unit_orbit_partition · Uses: G001, S016

S018 · implies

Before

complete disjoint unit orbits=[[1, 3, 9, 13, 11, 5]]

After

phi=6=1·6; remainder=0

Conditions: none

The unit set is partitioned into equal-length orbits, so order divides phi; equality or a primitive-root claim does not follow.

Step identifiers and dependencies

Rule: order_divides_totient · Uses: G001, S017

Reverse checks

  • S018 · premise_and_result_audit — Order is the first positive return to1; check n≥2 and coprimality first, and do not assert order=phi.
  • S017 · premise_and_result_audit — Order is the first positive return to1; check n≥2 and coprimality first, and do not assert order=phi.
  • S016 · premise_and_result_audit — Order is the first positive return to1; check n≥2 and coprimality first, and do not assert order=phi.
  • S015 · premise_and_result_audit — Order is the first positive return to1; check n≥2 and coprimality first, and do not assert order=phi.
  • S014 · premise_and_result_audit — Recompute power product at k=6 with exact rational arithmetic, not rounded decimals.
  • S013 · premise_and_result_audit — Order is the first positive return to1; check n≥2 and coprimality first, and do not assert order=phi.
  • S012 · premise_and_result_audit — Recompute power product at k=5 with exact rational arithmetic, not rounded decimals.
  • S011 · premise_and_result_audit — Order is the first positive return to1; check n≥2 and coprimality first, and do not assert order=phi.
  • S010 · premise_and_result_audit — Recompute power product at k=4 with exact rational arithmetic, not rounded decimals.
  • S009 · premise_and_result_audit — Order is the first positive return to1; check n≥2 and coprimality first, and do not assert order=phi.
  • S008 · premise_and_result_audit — Recompute power product at k=3 with exact rational arithmetic, not rounded decimals.
  • S007 · premise_and_result_audit — Order is the first positive return to1; check n≥2 and coprimality first, and do not assert order=phi.
  • S006 · premise_and_result_audit — Recompute power product at k=2 with exact rational arithmetic, not rounded decimals.
  • S005 · premise_and_result_audit — Order is the first positive return to1; check n≥2 and coprimality first, and do not assert order=phi.
  • S004 · premise_and_result_audit — Recompute power product at k=1 with exact rational arithmetic, not rounded decimals.
  • S003 · premise_and_result_audit — Order is the first positive return to1; check n≥2 and coprimality first, and do not assert order=phi.
  • S002 · premise_and_result_audit — Order is the first positive return to1; check n≥2 and coprimality first, and do not assert order=phi.
  • S001 · premise_and_result_audit — Order is the first positive return to1; check n≥2 and coprimality first, and do not assert order=phi.

Result

(6, 6, Yes, [[1, 3], [2, 9], [3, 13], [4, 11], [5, 5], [6, 1]], ord_n_a_divides_phi_n_without_claiming_equality_or_primitive_root)

The full substitutions and premise audits recover the original answer, retaining its field order and verdict meanings.

This question review and source binding

Review date: 2026-10-26

Original questions, answers, step expressions, numeric ASTs and historical records are retained. Source candidate labels remain historical and are not overwritten as formal proof.

Source hashes and review receipts
  • input commit: 0f7be61e2c22317a4075561dc822c87d881a50db
  • original question SHA-256: 4b9a6f89f0232e68f8a9d1429b697d0960bc9fb191e2cd76f36d6ed8e2943c13
  • candidate record SHA-256: 1ad586aa0134d260e7ecbab19939afad582212fe351cc62c62ece7685f79bb87
  • semantic review receipt SHA-256: 6c2c6d46aded7582a11ac41a8c0b3bdde2669a53bdb6e796eea2039994a02772
  • question-first witness SHA-256: 77e43898df9efdbf8094ad81fe4ab91cf4b4bd82f481eb9b4699b73cb4da612b
  • Lean: NOT_RUN · human review: NOT_PERFORMED
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