Startseite The ranks of (a,b)-Fibonacci sequences and congruences for certain partition functions and Ramanujan's mock theta functions
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The ranks of (a,b)-Fibonacci sequences and congruences for certain partition functions and Ramanujan's mock theta functions

  • Ernest X. W. Xia EMAIL logo
Veröffentlicht/Copyright: 13. Januar 2025

Abstract

In this paper, employing some identities due to Newman, we present a new method for discovering infinite families of congruences and strange congruences for c ( n ) which is defined by

n = 0 c ( n ) q n = k = 1 ( 1 - q k ) r ( 1 - q k t ) s .

Here r , s , t are some integers with t > 1 . By our method, in order to discover infinite families of congruences modulo M for c ( n ) , it suffices to compute the ranks of ( a , b ) -Fibonacci sequences modulo M. As applications, we establish many infinite families of congruences and strange congruences for some Ramanujan’s mock theta functions and certain partition functions, such as, a partition function related to mock theta function ω ( q ) and broken k-diamond partitions.

MSC 2020: 05A17; 11P83

Communicated by Freydoon Shahidi


Award Identifier / Grant number: 12371334

Funding statement: This work was supported by the National Science Foundation of China (no. 12371334) and the Natural Science Foundation of Jiangsu Province of China (no. BK20221383).

Acknowledgements

The author would like to express his sincere gratitude to the anonymous referee for his/her careful reading of the manuscript and many constructive suggestions.

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Received: 2024-05-22
Revised: 2024-09-08
Published Online: 2025-01-13
Published in Print: 2025-06-01

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Heruntergeladen am 21.9.2025 von https://www.degruyterbrill.com/document/doi/10.1515/forum-2024-0240/html
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