Explore related knowledge and questions →

Question 1578: A Typed Finite State and Its Canonical Residue Update

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

Return to catalogue page 8

← Question derivation index · Original question batch

R0002-01578 · q-20261013-advance-20261020-r01-discrete-dynamical-system-0003

Original question and givens

Use the complete finite self-map on Fin(7)={0,…,6} given by T(x)=(a*x+b) mod 7, a=-5, b=-7. Choose the least nonnegative residue, including for negative a*x+b. Time is discrete, indexed from 0; a finite orbit is not a general stability result. x=2. Give (modulus, a, b, x, T(x)).

  • G001 — Use the complete finite self-map on Fin(7)={0,…,6} given by T(x)=(a*x+b) mod 7, a=-5, b=-7. Choose the least nonnegative residue, including for negative a*x+b. Time is discrete, indexed from 0; a finite orbit is not a general stability result. x=2. Give (modulus, a, b, x, T(x)).

Definition and scope

Use the original question domain, assumptions and cited MKO definitions. This item has second-context mathematical and bilingual review, with the model, answer and every arithmetic step independently recomputed from the original parameters; the source question remains a candidate.

Step-by-step derivation

S001 · implies

Before

X={0 through 6}; T(x)=(-5x+(-7)) mod 7

After

remainder representative always lies in X

Conditions: none

Fix the full finite state carrier and the same update rule;negative integers also use the standard remainder from0 through n−1.

Step identifiers and dependencies

Rule: finite_total_map · Uses: G001

S002 · calculation

Before

one step: a·x := mul(-5, 2)

After

one step: a·x = -10

Conditions: none

Multiply the original coefficient by the current state;do not clip negative values to0.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S001

S003 · calculation

Before

one step: a·x+b := sum(-10, -7)

After

one step: a·x+b = -17

Conditions: none

Add the same offset before reducing modulo n.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S002

S004 · implies

Before

reduce -17 modulo 7

After

-17=-3·7+4

Conditions: none

The integer identity together with0≤remainder<n determines the next state.

Step identifiers and dependencies

Rule: euclidean_remainder · Uses: G001, S003

S005 · implies

Before

x=2

After

T(x)=4∈X

Conditions: none

This computes one update,not a whole orbit or a fixed-point classification.

Step identifiers and dependencies

Rule: state_membership · Uses: G001, S004

Reverse checks

  • S005 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S004 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
  • S003 · premise_and_result_audit — Recompute one step: a·x+b with exact rational arithmetic, not rounded decimals.
  • S002 · premise_and_result_audit — Recompute one step: a·x with exact rational arithmetic, not rounded decimals.
  • S001 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.

Result

(7, -5, -7, 2, 4)

The full substitutions and premise checks give the original answer; source identity,format and status are unchanged.

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: 7264ed134d278c84ea78169a2673ff9bfae7577d8b670a043aa6cbe71584d7aa
  • candidate record SHA-256: 615d57f05d3833a0821ef433192dc59233efb1cb130e75807f906e38bcb8196b
  • semantic review receipt SHA-256: 340d74dcc6e37df6249594a0b79a9ee2af804337b7847478b3c1342af9722861
  • question-first witness SHA-256: 9a06233d190d31a16f13fb03b6c3ceba4cbb748fff6c997941f66ab1888dcca8
  • Lean: NOT_RUN · human review: NOT_PERFORMED
Same-source full JSON