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Question 977: Undefined Nonunit/Modulus Cases Differ from Order One and Negative Residues

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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P1000-0977 · q-20261015-advance-20261116-r07-multiplicative-order-mod-n-0077

Original question and givens

Use exact modulus n=1 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. Mode=invalid_modulus. Give (mode, n, a, normalized_residue_or_null, gcd_or_null, unit_qualified, power_rows_or_null, order_or_undefined, boundary).

  • G001 — Use exact modulus n=1 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. Mode=invalid_modulus. Give (mode, n, a, normalized_residue_or_null, gcd_or_null, unit_qualified, power_rows_or_null, order_or_undefined, boundary).

Definition and scope

For n<2 or a noncoprime residue the order is undefined; residue 1 has order 1; normalize a negative representative into [0,n) first.

Step-by-step derivation

S001 · implies

Before

n=1; 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

n=1<2

After

modulus qualification fails

Conditions: none

This multiplicative-order contract does not accept this modulus.

Step identifiers and dependencies

Rule: invalid_order_modulus · Uses: G001, S001

S003 · implies

Before

outside the declared unit-group domain

After

residue=null; gcd=null; power table=null

Conditions: none

These nulls mean uncomputed contract fields, not that every arithmetic operation modulo1 is meaningless.

Step identifiers and dependencies

Rule: no_out_of_scope_arithmetic · Uses: G001, S002

S004 · implies

Before

qualification=false

After

order=undefined

Conditions: none

Do not invent order0 or substitute a totient value.

Step identifiers and dependencies

Rule: undefined_order_boundary · Uses: G001, S003

Reverse checks

  • S004 · premise_and_result_audit — Order is the first positive return to1; check n≥2 and coprimality first, and do not assert order=phi.
  • 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

(invalid_modulus, 1, 3, null, null, No, null, undefined, mode_specific_multiplicative_order_boundary)

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: 2bf10960f88ccccda151695de354a95a465ad8974c02b1ccba89675c0d0e474b
  • candidate record SHA-256: 7cc131338bc49d8bdc7eb967fee9614eac3e7117cf408453a542dfa363b54716
  • semantic review receipt SHA-256: 6c2c6d46aded7582a11ac41a8c0b3bdde2669a53bdb6e796eea2039994a02772
  • question-first witness SHA-256: 77e43898df9efdbf8094ad81fe4ab91cf4b4bd82f481eb9b4699b73cb4da612b
  • Lean: NOT_RUN · human review: NOT_PERFORMED
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