English
Related papers

Related papers: Notes for Neighborly Partitions

200 papers

We examine an identity originally stated in Ramanujan's ``lost notebook'' and first proven algebraically by Andrews and combinatorially by Kim. We give two independent combinatorial proofs and interpretations of this identity, which also…

Combinatorics · Mathematics 2009-11-04 Paul Levande

We prove that there exist bipartite Ramanujan graphs of every degree and every number of vertices. The proof is based on analyzing the expected characteristic polynomial of a union of random perfect matchings, and involves three…

Combinatorics · Mathematics 2015-06-01 Adam W. Marcus , Nikhil Srivastava , Daniel A. Spielman

Recently, Andrews, Hirschhorn and Sellers have proven congruences modulo 3 for four types of partitions using elementary series manipulations. In this paper, we generalize their congruences using arithmetic properties of certain quadratic…

Number Theory · Mathematics 2021-02-03 Jeremy Lovejoy , Robert Osburn

We investigate properties of attainable partitions of integers, where a partition $(n_1,n_2, \dots, n_r)$ of $n$ is attainable if $\sum (3-2i)n_i\geq 0$. Conjecturally, under an extension of the Cohen and Lenstra heuristics by Holmin et.…

Number Theory · Mathematics 2021-11-24 Kathleen Petersen , James Sellers

Ballantine--Beck--Feigon--Maurischat introduced the subsum polynomial \[ \operatorname{sp}(\lambda,x):=\prod_i (1+x^{\lambda_i}) \] attached to an integer partition $\lambda$, and studied rational functions obtained by summing reciprocals…

Combinatorics · Mathematics 2026-05-25 Evan Chen , Ken Ono , Jujian Zhang

For a given prime $p$, we study the properties of the $p$-dissection identities of Ramanujan's theta functions $\psi(q)$ and $f(-q)$, respectively. Then as applications, we find many infinite family of congruences modulo 2 for some…

Combinatorics · Mathematics 2013-02-18 Suping Cui , Nancy Shanshan Gu

We survey divisibility properties of the Fourier coefficients of modular functions inspired by Ramanujan. Then using recent results of the generalized Hecke operator on harmonic Maass functions and known divisibility of Fourier coefficients…

Number Theory · Mathematics 2020-12-18 Soon-Yi Kang

Let $a_k(n)$ denote the number of partitions of $n$ wherein even parts come in only one color, while the odd parts may be ``colored" with one of $k$ colors, for fixed $k$. In this note, we find some congruences for $a_k(n)$ in the spirit of…

Number Theory · Mathematics 2026-01-21 Anjelin Mariya Johnson , James A. Sellers , S. N. Fathima

Let $\bar{a}_s(n)$ denote the number of partitions of $n$, wherein each odd part is multicolored (atmost $s\ge 1$ colors) and the first appearance of parts may be overlined. In this paper, we establish new families of congruences modulo…

Number Theory · Mathematics 2026-05-21 M. P. Thejitha , S. N. Fathima

We establish infinite families of congruences modulo arbitrary powers of $2$ for the three restricted partition functions $M(n), T^\ast(n)$, and $P^\ast(n)$ introduced by Pushpa and Vasuki by employing elementary $q$-series techniques.…

Number Theory · Mathematics 2026-02-20 Russelle Guadalupe

It is known that $q$-orthogonal polynomials play an important role in the field of $q$-series and special functions. During studying Dyson's "favorite" identity of Rogers--Ramanujan type, Andrews pointed out that the classical orthogonal…

Number Theory · Mathematics 2021-12-28 Lisa H. Sun

In this paper, we establish a connection between Rogers-Ramanujan-Gordon type overpartitions to lattice paths with four kinds of unitary steps. By establishing the bijective relationship between overpartitions and lattice paths, we…

Combinatorics · Mathematics 2025-01-29 Diane Y. H. Shi

We give another proof of the second Rogers-Ramanujan identity by Kashiwara crystals.

Quantum Algebra · Mathematics 2022-11-23 Shunsuke Tsuchioka

In 1944 Dyson defined the rank of a partition as the largest part minus the number of parts, and conjectured that the residue of the rank mod 5 divides the partitions of 5n+4 into five equal classes. This gave a combinatorial explanation of…

Number Theory · Mathematics 2020-12-15 Frank Garvan

Amdeberhan et al. (2024) introduced the notion of a generalized overcubic partition function $\overline a_c (n)$ and proved an infinite family of congruences modulo a prime $p\ge 3$ and some Ramanujan type congruences. In this paper, we…

Number Theory · Mathematics 2025-03-25 Adam Paksok , Nipen Saikia

A partition of degree $n$ is a decomposition $n=i_1+i_2+\dots+i_q$, where ${i_1,i_2,\dots,i_q}$ are positive integers called the parts of the partition. Let $\lambda>0$ be an integer. The partition is said to be a $\lambda$--partition if…

Combinatorics · Mathematics 2017-03-22 F. V. Weinstein

We are interested in identities between Littlewood-Richardson coefficients, and hence in comparing different tensor product decompositions of the irreducible modules of the linear group GL n (C). A family of partitions-called…

Combinatorics · Mathematics 2021-07-09 Maxime Pelletier , Ressayre Nicolas

We prove combinatorially some identities related to Euler's partition identity (the number of partitions of $n$ into distinct parts equals the number of partitions of $n$ into odd parts). They were conjectured by Beck and proved by Andrews…

Combinatorics · Mathematics 2018-07-02 Cristina Ballantine , Richard Bielak

Andrews and the third author recently studied congruences for certain restricted two-color partitions. They made two conjectures for Ramanujan-type congruences and a vanishing identity for the limiting sequence. In this paper, we settle…

Number Theory · Mathematics 2026-04-03 Koustav Banerjee , Kathrin Bringmann , Mohamed El Bachraoui

We set up a combinatorial framework for inclusion-exclusion on the partitions into distinct parts to obtain an alternative generating function of partitions into distinct and non-consecutive parts. In connection with Rogers-Ramanujan…

Combinatorics · Mathematics 2020-04-14 Kağan Kurşungöz