RESEARCH / Focused target
Hanna's second congruence for A365771
RELEASED FOUNDATIONS / PROPOSED CONNECTION
Research connections
All source anchors (1)
- Hanna's second congruence modulo fiveReleased anchor
Problem
The question
OEIS A365771 revision 23, Comments, states:
Conjectures: given A033042 is the sums of distinct powers of 5, then (2) a(5*A033042(n) + 1) == 2 (mod 5) for n > 0,
Preregistration: #18657.
Statement echo
Every positive $m$ in A033042 satisfies $a(5m+1)\bmod5=2$.
The sequence and digit predicate are exactly D5.S1.Recurrence.Residue.HannaA365771.a
and D5.S1.Recurrence.Residue.HannaA365771.InA033042. The claim uses natural-number arithmetic.
Motivation
Our foothold
This is one of the three residue assertions in A365771; the family dossier is
hanna365771-mod5.md, and the source note is
Library/Digit/hanna2023a365771.md.
Gap
Missing bridges
The source labels the assertion a conjecture. The preregistration records the source and literature screen.
Search completeness and publication priority are ASSUMED-UNVERIFIED.
Route
Proposed approach
The same-delivery HannaA365771.digits_step and HannaA365771.residue_classification
supply the digit decomposition and the residue. The shared module is not a previously frozen dependency.
The positive integer $5m+1$ has remainder one and quotient $m$ upon division by five.
Its digits therefore satisfy the same zero/one condition, and the classification gives residue two.
Falsifier
What would falsify this route
An input satisfying the claim's hypotheses with a different residue would refute the assertion. A source-to-definition mismatch would invalidate fidelity.
Evidence
Evidence to collect
Kernel-checked settling declaration: D5.S1.Recurrence.Residue.HannaA365771Two.result.
The module's admission basis is open-problem-resolution (#18657; Proved) and utility is none.
Its Scribe records a Proved resolution of this dossier.
Four-slot escape registration for this result is unfinished under
issue #22018.
No successful Reg registration is claimed.
The family dossier contains the immutable experiment reference and the finite computed readings.
Triage
Scope assessment
- Proved: kernel-checked
HannaA365771Two.resultproves the exact claim. - Proved: the complete positive-index classification and multinomial indicator are the
kernel-checked
HannaA365771.residue_classificationand privateHannaA365771.M_mod. - Computed: the family dossier's pinned checker passes through $n=6000$ and checks the scaled identity for $1\leq n<3000$; this is finite evidence.
- Open: higher powers of five, other primes and the unbounded stronger valuation comparison.
What the settlement shows
The digit classification determines the residue for every input of this assertion; no numerical upper bound is a hypothesis. The other two congruences have their own kernel-checked results in the same family. The stronger valuation comparison is not asserted in Lean.
ASSUMED-UNVERIFIED
Unverified assumptions
Literature-search completeness, publication priority and source-to-definition identification retain the boundaries stated in the family dossier.