On a restricted $m$-non-squashing partition function

Rødseth, Øystein ; Sellers, James A.

Journal of integer sequences, Tome 8 (2005) no. 5.

Résumé

Summary: For a fixed integer $m\ge 2$, we say that a partition $n=p_1+p_2+\cdots +p_k$ of a natural number $n$ is $m$-non-squashing if $p_1\ge 1$ and $(m-1)(p_1+\cdots +p_{j-1})\le p_j$ for $2\le j\le k$. In this paper we give a new bijective proof that the number of $m$-non-squashing partitions of $n$ is equal to the number of $m$-ary partitions of $n$. Moreover, we prove a similar result for a certain restricted $m$-non-squashing partition function $c(n)$ which is a natural generalization of the function which enumerates non-squashing partitions into distinct parts (originally introduced by Sloane and the second author). Finally, we prove that for each integer $r\ge 2$,$$ c(m^{r+1}n)-c(m^r n)\equiv0\pmod{m^{r-1}/d^{r-2}},$$ where $d=gcd(2,m)$.

Détail

Classification : 11P83, 05A17, 11P81
Mots-clés : partitions, m-non-squashing partitions, m-ary partitions, stacking boxes, congruences (Concerned with sequences and