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SUMS OF SQUARES AND PARTITION CONGRUENCES

Published online by Cambridge University Press:  18 March 2020

SU-PING CUI
Affiliation:
School of Mathematics and Statistics, Qinghai Normal University, Xining, Qinghai810008, PR China Academy of Plateau Science and Sustainability, Xining, Qinghai810008, PR China e-mail: jiayoucui@163.com
NANCY S. S. GU
Affiliation:
Center for Combinatorics, LPMC, Nankai University, Tianjin300071, PR China e-mail: gu@nankai.edu.cn

Abstract

For positive integers $n$ and $k$, let $r_{k}(n)$ denote the number of representations of $n$ as a sum of $k$ squares, where representations with different orders and different signs are counted as distinct. For a given positive integer $m$, by means of some properties of binomial coefficients, we derive some infinite families of congruences for $r_{k}(n)$ modulo $2^{m}$. Furthermore, in view of these arithmetic properties of $r_{k}(n)$, we establish many infinite families of congruences for the overpartition function and the overpartition pair function.

Type
Research Article
Copyright
© 2020 Australian Mathematical Publishing Association Inc.

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Footnotes

Communicated by M. Coons

This work was supported by the National Natural Science Foundation of China, the Fundamental Research Funds for the Central Universities of China, the Natural Science Foundation for Young Scientists of Qinghai Province and Outstanding Chinese, and the Foreign Youth Exchange Program of the China Association of Science and Technology.

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