Pith. sign in

REVIEW 1 major objections 8 references

Pascal-like Sprugnoli arrays

T0 review · 1 major / 0 minor · reviewed 2026-06-26 · grok-4.3

Pith's one-line read Palindromic Sprugnoli arrays fall into two families with closed-form entries and described inverses.

desk verdict Barry's note identifies two palindromic Sprugnoli array families and supplies closed forms plus inverse descriptions, which adds concrete formulas if the derivations check out. read the letter →

arxiv 2606.22070 v2 pith:IEVV56AR submitted 2026-06-20 math.CO

classification math.CO
keywords SprugnoliarrayspalindromicPascal-likeclosedformexpressionsinversemodulo2sequencesarithmeticcombinatorial
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper examines Sprugnoli arrays restricted to be palindromic, also termed Pascal-like. This restriction produces exactly two closely related families. Closed form expressions are supplied for every entry in both families. The form of the inverse array is described explicitly in each case. Reduction of the arrays modulo 2 produces arithmetic sequences.

What carries the argument

The palindromic restriction on standard Sprugnoli arrays, which isolates two families whose entries admit closed forms.

What would settle it

Computing a specific entry from a palindromic Sprugnoli array and finding that it matches neither of the two proposed closed forms would falsify the claim of exactly two families.

Watch

Extended reading notes

Core claim

In this note, we look at the structure and properties of palindromic or Pascal-like Sprugnoli arrays. We show that there are two closely related families of these arrays. We give closed form expressions for the elements of these families, and in each case, we describe the form of the inverse arrays. Finally, we consider the arrays modulo 2 and the resulting arithmetic sequences.

Load-bearing premise

The standard definition of Sprugnoli arrays permits a well-defined palindromic restriction that produces exactly two families with the stated closed forms and inverses.

Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit.

Referee Report

1 major / 0 minor

Summary. The manuscript examines palindromic or Pascal-like Sprugnoli arrays, asserting the existence of two closely related families. It claims to supply closed-form expressions for the array elements, describe the form of the corresponding inverse arrays in each case, and analyze the arrays reduced modulo 2, which are said to produce arithmetic sequences.

Significance. If the claimed closed forms and inverse descriptions were rigorously derived from the standard definition of Sprugnoli arrays and independently verified, the work would contribute explicit formulas and structural insights to the study of combinatorial arrays. The modulo-2 analysis might connect to known arithmetic-progression phenomena in Pascal-like triangles, but the absence of any derivations, examples, or verification prevents assessment of whether these contributions are realized.

major comments (1)
  1. [Abstract] Abstract: the central claims (existence of closed forms for the two families, explicit description of the inverses, and the modulo-2 arithmetic sequences) are asserted without any derivation, generating function, recurrence, or explicit formula supplied in the text. This is load-bearing for the entire contribution, as the manuscript consists solely of the abstract and therefore provides no mathematical support for the stated results.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for the detailed report. We acknowledge that the submitted manuscript consisted only of the abstract and contained no derivations or supporting material. We will revise the manuscript substantially to address this.

read point-by-point responses
  1. Referee: [Abstract] Abstract: the central claims (existence of closed forms for the two families, explicit description of the inverses, and the modulo-2 arithmetic sequences) are asserted without any derivation, generating function, recurrence, or explicit formula supplied in the text. This is load-bearing for the entire contribution, as the manuscript consists solely of the abstract and therefore provides no mathematical support for the stated results.

    Authors: We agree with this assessment. The submitted version was incomplete and consisted solely of the abstract. In the revised manuscript we will supply the closed-form expressions for the two families of palindromic Sprugnoli arrays, derive them from the standard definition, provide explicit descriptions of the inverse arrays, and include the modulo-2 analysis together with generating functions, recurrences, and explicit verification examples. revision: yes

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity detected

full rationale

The provided abstract and summary describe claims of closed-form expressions, inverse array forms, and modulo-2 sequences for two families of palindromic Sprugnoli arrays, but contain no equations, derivations, or self-citations that could be inspected for reduction to inputs by construction. No load-bearing steps are visible that match any of the enumerated circularity patterns, and the standard definition of Sprugnoli arrays is treated as external prior literature. The derivation chain is therefore self-contained against external benchmarks with no evidence of fitted inputs renamed as predictions or ansatzes smuggled via self-citation.

Assumptions & free parameters 0 free parameters · 1 assumptions · 0 invented entities

The central claims rest on the pre-existing definition of Sprugnoli arrays and the assumption that a palindromic restriction yields exactly two families with the stated algebraic properties.

assumptions (1)
  • domain assumption Sprugnoli arrays are defined according to the standard construction in the prior combinatorial literature.
    The paper invokes this definition to introduce the palindromic variants.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Pascal-like Sprugnoli arrays." pith.science (2026). https://pith.science/paper/IEVV56AR

@misc{pith2026260622070,
  author       = {Pith},
  title        = {Pith review of: Pascal-like Sprugnoli arrays},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/IEVV56AR}},
  note         = {Machine review of arXiv:2606.22070}
}
abstract

In this note, we look at the structure and properties of palindromic or Pascal-like Sprugnoli arrays. We show that there are two closely related families of these arrays. We give closed form expressions for the elements of these families, and in each case, we describe the form of the inverse arrays. Finally, we consider the arrays modulo $2$ and the resulting arithmetic sequences.

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

8 extracted references · 1 canonical work pages

  1. [1]

    A new group in the Riordan family of matrix groups: the Sprugnoli group

    P. Barry, A new group in the Riordan family of matrix groups: the Sprugnoli group, https://arxiv.org/abs/2605.16633

  2. [2]

    Barry,Riordan Arrays: a Primer, Logic Press, 2017

    P. Barry,Riordan Arrays: a Primer, Logic Press, 2017

  3. [3]

    Barry, On integer-sequence-based constructions of generalized Pascal triangles,J

    P. Barry, On integer-sequence-based constructions of generalized Pascal triangles,J. Integer Seq.,9(2006), Article 06.2.4

  4. [4]

    Corsani, D

    C. Corsani, D. Merlini, and R. Sprugnoli, Left-inversion of combinatorial sums,Discrete Math.,180(1998) 107–122

  5. [5]

    Shapiro, R

    L. Shapiro, R. Sprugnoli, P. Barry, G.-S. Cheon, T.-X. He, D. Merlini, and W. Wang, The Riordan Group and Applications, Springer, 2022

  6. [6]

    L. W. Shapiro, S. Getu, W. J. Woan, and L. C. Woodson, The Riordan group,Discr. Appl. Math.,34(1991), 229–239

  7. [7]

    N. J. A. Sloane,The On-Line Encyclopedia of Integer Sequences. Published electroni- cally athttp://oeis.org, 2025

  8. [8]

    N. J. A. Sloane, The On-Line Encyclopedia of Integer Sequences,Notices Amer. Math. Soc.50(2003), 912–915. 16 2020Mathematics Subject Classification: Primary 15B36; Secondary 05A15, 11B83, 15A30, 20H25. Keywords:Pascal triangle, Pascal-like matrix, Riordan group, Sprugnoli group, generating function. (Concerned with sequence A000027, A000045, A000073, A000...

Pith tools

Reviewed June 26, 2026 · model on record in the stance chip above.