English

New Congruences of Partitions With Odd Parts Distinct

Number Theory 2014-11-03 v2

Abstract

Let pod(n)\mathrm{pod}(n) denote the number of partitions of nn with odd parts distinct, and rk(n){{r}_{k}}(n) be the number of representations of nn as sum of kk squares. We find the following two arithmetic relations: for any integer n0n\ge 0, pod(3n+2)2(1)n+1r5(8n+5)(mod9),\mathrm{pod}(3n+2)\equiv 2{{(-1)}^{n+1}}{{r}_{5}}(8n+5) \pmod{9}, and pod(5n+2)2(1)nr3(8n+3)(mod5).\mathrm{pod}(5n+2)\equiv 2{{(-1)}^{n}}{{r}_{3}}(8n+3) \pmod{5}. From which we deduce many interesting congruences including the following two infinite families of Ramanujan-type congruences: for a{11,19}a \in \{11, 19\} and any integers α1\alpha \ge 1 and n0n \ge 0, we have pod(52α+2n+a52α+1+18)0(mod5).\mathrm{pod}\Big({{5}^{2\alpha +2}}n+\frac{a \cdot {{5}^{2\alpha +1}}+1}{8}\Big)\equiv 0 \pmod{5}.

Keywords

Cite

@article{arxiv.1407.5436,
  title  = {New Congruences of Partitions With Odd Parts Distinct},
  author = {Liuquan Wang},
  journal= {arXiv preprint arXiv:1407.5436},
  year   = {2014}
}

Comments

6 pages