On the number of missing integers in partitions
Pith reviewed 2026-05-10 15:35 UTC · model grok-4.3
The pith
Partitions and overpartitions admit counting functions by number of missing integers that satisfy congruences and bias conjectures.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
A missing integer in a partition is any positive integer smaller than the largest part that does not appear among the parts. The authors introduce the functions that count partitions of n having exactly k missing integers, both for ordinary partitions and for overpartitions. They prove congruences satisfied by two pairs of these functions and state three explicit conjectures that compare the functions in a bias-type manner.
What carries the argument
The counting functions that record the number of partitions (ordinary and over) of n having exactly k missing integers, where a missing integer is a positive integer less than the largest part and absent from the partition.
If this is right
- The generating functions attached to the new counting functions admit factorizations or relations that make the congruences transparent.
- Linear combinations of the functions for different k are divisible by small moduli.
- The bias inequalities distinguish the growth rates of the counts for even and odd numbers of missing integers.
- The same pattern of congruences appears in both the unrestricted and overpartition cases.
Where Pith is reading between the lines
- The missing-integer statistic could be applied to other restricted classes such as distinct-part partitions to test whether similar congruences appear.
- Proving the bias conjectures would give an asymptotic explanation for why partitions tend to avoid or include certain integers in a non-uniform way.
- The framework offers a natural way to refine existing mex-generating-function identities by incorporating the total gap count rather than only the smallest gap.
Load-bearing premise
The newly defined counting functions for partitions with a fixed number of missing integers possess enough arithmetic structure to support exact congruences and the stated bias inequalities.
What would settle it
An explicit counterexample: an integer n together with computed values of the counting functions showing that at least one of the three conjectured inequalities fails for that n.
read the original abstract
In the preceding decade, Andrews and Newman resurrected the concept of a `minimal excludant' of a partition ($mex$, for short), namely, the least positive missing integer in a partition. Subsequently, several authors have not only studied its generalizations, analogues and the like but also connected the mex to several important partition statistics. In the present paper, we study the set of missing positive integers as a whole, in two different classes of partitions, namely, unrestricted partitions and overpartitions. To be precise, a $missing \ integer$ is a positive integer that is less than the largest part of a partition and which does not occur as a part. In particular, we examine the number of partitions with a given number of missing integers, determine congruences for two pairs of functions associated to them, and propose three bias type inequality conjectures for these functions.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper studies the set of missing positive integers (those less than the largest part but not appearing as parts) in unrestricted partitions and overpartitions. It defines and examines counting functions for the number of such partitions with a fixed number of missing integers, derives congruences for two pairs of associated functions, and proposes three bias-type inequality conjectures for these functions in both partition classes.
Significance. By extending the mex framework of Andrews and Newman to the total count of missing integers rather than the minimal one, the work introduces new arithmetic statistics on partitions. The explicit congruences, if rigorously established, add to the body of modular results in partition theory, while the bias conjectures offer testable predictions that could connect to existing inequalities on partition functions.
minor comments (3)
- [Introduction] §1 (Introduction): the definition of 'missing integer' should be stated with a formal notation (e.g., M(λ)) before any counting functions are introduced, to avoid ambiguity when the largest part is 1.
- [Abstract] The generating functions or recurrence relations used to obtain the congruences are not referenced by equation number in the abstract; adding a forward reference in the introduction would improve readability.
- [Computational evidence] Table or computational section: verify that the numerical checks supporting the three conjectures include sufficiently large n (e.g., beyond 100) and report the exact range tested.
Simulated Author's Rebuttal
We thank the referee for their positive assessment of our manuscript and for recommending minor revision. The referee's summary correctly captures the main contributions: extending the mex framework to count the total number of missing integers in partitions and overpartitions, establishing congruences for the associated generating functions, and proposing bias-type inequalities. Since the report lists no specific major comments under the MAJOR COMMENTS section, we have no individual points to address. We will use the minor revision to incorporate any editorial improvements for clarity and presentation.
Circularity Check
No significant circularity; derivation self-contained
full rationale
The paper introduces the concept of missing integers in partitions and overpartitions by direct definition (positive integers less than the largest part that do not occur as parts). It then defines associated counting functions for partitions with a fixed number of such missing integers. Congruences for pairs of these functions are determined, which in partition theory typically follow from generating function identities or modular form techniques rather than from fitted parameters or self-referential definitions. Three bias-type inequalities are explicitly proposed as conjectures, not claimed as proven derivations. No load-bearing steps reduce by construction to inputs, self-citations, or renamed known results; the work extends prior mex studies via new but independently defined statistics.
Axiom & Free-Parameter Ledger
axioms (1)
- domain assumption Standard definitions of unrestricted partitions and overpartitions as used in the literature on mex.
Reference graph
Works this paper leans on
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N. J. A. Sloane, Online Encyclopedia of Integer Sequences,https://oeis.org/. Subhash Chand Bhoria, Department of Mathematics, Pt. Chiranji Lal Sharma Gov- ernment College, Urban Estate, Sector-14, Karnal, Haryana - 132001, India. Email address:scbhoria89@gmail.com Pramod Eyyunni, Department of Mathematics, Birla Institute of Technology and Science Pilani,...
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