RESEARCH / Focused target
Absolute Hermite coefficient modes: the complete A381524 difference assertion
RELEASED FOUNDATIONS / PROPOSED CONNECTION
Research connections
All source anchors (1)
- D5/S3/Analytic/Polynomial/HermiteAbsoluteMode.resultAbsent from this graph
Problem
The question
OEIS A381524, revision 18, by Mike Sheppard (2025), defines:
Smallest exponent of x of maximal coefficient (ignoring signs) in Hermite polynomial of order n.
Its independently printed Comments assertion is:
Conjecture: Differences are either +1 or -1.
The offset is zero. Let $H_n$ be the physicists Hermite polynomial represented
by the original HermiteSignedMode.physicistsHermite, and let $b(n)$ be the
least $j\in{0,\ldots,n}$ maximizing $|[x^j]H_n|$. The complete event is
$$ \begin{aligned} \forall n\in\mathbb N,\quad &b(n)\le n,\ &\forall k\le n,\quad |[x^k]H_n|\le |[x^{b(n)}]H_n|,\ &\forall k\le n,\quad |[x^k]H_n|=|[x^{b(n)}]H_n|\ \Longrightarrow\ b(n)\le k,\ &b(n+1)-b(n)\in{1,-1}\quad\text{in }\mathbb Z. \end{aligned} $$
Both selector values are cast to integers before subtraction. Every natural
order, including zero, every exponent from zero through the order, parity
zeros and all ties are included. The source's HermiteH convention and
examples fix physicists normalization: $b(5)=3$, and $b(8)=2$ chooses the
smaller of the tied exponents two and four. The claim is the one entire
Differences assertion with its selector certificate, without a uniqueness
premise, finite cutoff or asymptotic qualification.
Motivation
Our foothold
This is a Tier 1 explicit recent OEIS conjecture under the repository's source classification, not an arXiv assertion or a difficulty measurement. The exact whole event is preregistered at https://github.com/the-omega-institute/trureturing/issues/25789#issuecomment-6586906062. The neighboring signed selector in A381423 has differences $1,-3$ and is a separate result. Its helpers and the source's separate tie-classification assertion are outside this dossier's resolution claim.
Gap
Missing bridges
The accepted bounded source examination found the same definition, Comments assertion, examples and offset in revision 18 and the retrieved current revision 18. The source's programs and examples supply conventions and finite data, not a universal proof. No exact whole-target solver was identified in the inspected scope:
- Exact A381524 and maximal-coefficient phrase queries in arXiv metadata each returned zero matches. The broader Hermite mode query inspected only the first 30 of 540 metadata results; 510 remained uninspected. A separate coefficient query inspected 21 titles and three selected abstracts, without a full-text screen of those papers.
- arXiv:1909.03874v2 was checked through bounded term scans of 11 TeX members and selected normalization/coefficient passages; arXiv:1801.07980v2 through bounded term scans and its initial convention/recurrence. Their probabilists Wronskian normalization is not an established mode-preserving bridge.
- arXiv:2204.07526v2 was checked through bounded term scans of 16 TeX/Bib members and selected orthonormal-Hermite pointwise-bound passages. The specific Dudeja–Hsu Lemma 35 remains unidentified; this inspection does not complete the screen of that citation.
- GitHub code-search requests returned HTTP 403. The inspected public Problems page displayed 1000 of 1663 entries. Three selected third-party Lean sources had differing pin and license limits; their bounded inspection established no exact admissible whole-target supplier.
Original D5 public/private declarations and pinned Mathlib were examined before local proof development. The original coefficient extraction and finite-maximum interfaces supply part of the argument. The signed mode's concrete $n-4r$ thresholds do not directly instantiate to the absolute $n-2r$ family. Within-row maximality alone does not supply the adjacent-order transition. These are bounded reuse findings, not worldwide absence or current-openness claims.
Route
Proposed approach
The proof uses the original physicistsHermite, signedCoeff and
HermiteSignedMode.polynomial_coeff, whose original statement and proof are
preserved with only the consumed extraction made public. For exponent
$n-2r$, its absolute coefficient is a positive weight $w(n,r)$ when $2r\le n$;
the other parity coefficients are zero. Adjacent weights obey
$$ 4(r+1)w(n,r+1)=(n-2r-1)(n-2r)w(n,r) \qquad(2(r+1)\le n). $$
The threshold $2r\le n$ and $4r\le(n-2r+1)(n-2r+2)$ is the nondecrease test from the preceding weight. Its true indices form an initial segment. Induction proves global maximality at the last true index and strict decrease beyond it. Choosing that last index reverses to the least exponent among all tied maxima. Threshold persistence and rollback across adjacent orders bound the index increment by zero or one; $b(n)=n-2\operatorname{mode}(n)$ then gives the exact integer difference $1$ or $-1$. The same argument includes order zero.
Falsifier
What would falsify this route
A natural order at which the defined selector fails any full-range maximum or least-tie obligation, or whose adjacent integer difference is neither $1$ nor $-1$, would falsify the complete formal event. Finite examples alone cannot establish it. No signed-selector, uniqueness or asymptotic surrogate is substituted for this test.
Evidence
Evidence to collect
The owning Scribe binds exactly one OpenProblemResolutionClaim(Proved) to
D5/S3/Analytic/Polynomial/HermiteAbsoluteMode.result for this slug. Its exact
frozen identities are:
- Module:
D5/S3/Analytic/Polynomial/HermiteAbsoluteMode, statement identitysha256:5303c1213e0ff3c9430ffb07325d3f6c48fb03e94c18384b1aeaea180d1d8fe5. - Whole theorem
result, statement identitysha256:c3e260b5a52e394f99f879492ca4b33fa516e5615e07fe37395a0375d9a27e68. - Complete proposition
claim, statement identitysha256:facac8b9042d55112c726de672d9b824c51b2eb37993305f89a6f9d90b8a572f.
The accepted independent conclusions use the unchanged compiled mathematical
evidence with noSorry and axiom closure Classical.choice, Quot.sound,
propext. The admission basis is open-problem-resolution for the whole
preregistered external event; escape_witness: none and utility: none.
Proof shape is separate from that admission basis. The accepted per-theorem
classification and actual live consumers are:
| Declaration suffix | proof_shape | Live consumers |
| --- | --- | --- |
| zero_candidate | bind-only | mode nonempty certificate |
| mode_rises | bind-only | mode_step, weight_le_mode, b_spec, result |
| le_mode | bind-only | mode_step, weight_le_mode, weight_lt_mode |
| second_mono | bind-only | rises_lower, rises_next, rises_previous |
| rises_lower | bind-only | weight_le_mode |
| rises_next | bind-only | mode_step |
| rises_previous | bind-only | mode_step |
| mode_step | bind-only | result integer-jump conjunct |
| weight_pos | bind-only | adjacent_le, b_spec exclusion of zeros |
| adjacent | bind-only | adjacent_le |
| adjacent_le | bind-only | weight_le_mode, weight_lt_mode |
| weight_le_mode | content | weight_lt_mode, b_spec maximality |
| weight_lt_mode | content | b_spec least-tie conjunct |
| coefficient_cases | bind-only | both selector conjuncts of b_spec |
| b_spec | content | result selector conjunct |
| result | content | Reg source_registration actual law and dependence |
Definitions and their decidability instance are consumed type/definition
support, not additional theorem content. The existing extraction
HermiteSignedMode.polynomial_coeff is bind-only, with preserved statement
identity sha256:4295bdb6223b1da40e22523dcdbb52f92642fe627927807633e64e1d34b7cc19,
and is consumed by the original a_spec and absolute b_spec. It is not a new
mathematical result.
The sole newly authored public D5 theorem, result, has the accepted
declared_validated source-family registration in
Reg/D5/S3/Analytic/Polynomial/HermiteAbsoluteMode.lean, using the enrolled
DependentFamily.realize template. Its state and output are natural numbers:
the readout is the entire $\mathbb N\to\mathbb N$ selector family, without
truncation. Source equivalence reconstructs the complete conjunction;
variation and sensitivity use the rejected constant-zero family, and actual
dependence uses indices zero and one. Reg rejected_law is a consumed
bind-only audit helper. Empty anchors impose no hidden finite restriction.
Continuation is unknown, which asserts neither undecidability nor
inexhaustibility. This audit evidence is separate from mathematical
proof shape and supplies no invented escape witness.
Triage
Scope assessment
theorem. The proved formal result contains both the complete all-natural
selector certificate and the entire adjacent-difference assertion. Its
mechanism is the last nondecreasing weight threshold together with its
adjacent-order persistence and rollback. Ties are retained rather than
excluded. No uniqueness theorem, tie classification, asymptotic result or
generalized mode-transition theorem is asserted here; those remain outside
this event. The source citation and search limits below remain unresolved.
ASSUMED-UNVERIFIED
Unverified assumptions
Source-to-Lean fidelity is a content correspondence supported by the accepted independent source/form/mirror review, not a kernel proof about OEIS prose. The universal reading combines the source's unqualified Differences assertion with its zero offset; OEIS does not literally print a forall formula. The author line is dated February 26, 2025, whereas the database creation field is March 16, 2025; those are distinct provenance fields.
The specific Dudeja–Hsu Lemma 35 remains unidentified. The metadata, pagination, code-search, selected-passage and third-party pin/license limits in Gap remain in force. No exhaustive search, worldwide current openness, priority or originality certification follows from them. No further result depending on the source's separate tie conjecture is claimed. The Library source is citation-only, and its examples/programs are not proof evidence.