## The Folsom-Ono grid contains only integers

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- by Sander Zwegers
- Proc. Amer. Math. Soc.
**137**(2009), 1579-1584 - DOI: https://doi.org/10.1090/S0002-9939-08-09684-6
- Published electronically: November 18, 2008
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## Abstract:

In a recent paper, Folsom and Ono constructed a canonical sequence of weight 1/2 mock theta functions and a canonical sequence of weight 3/2 weakly holomorphic modular forms, both using Poincaré series. They show a remarkable symmetry in the coefficients of these functions and conjecture that all the coefficients are integers. We prove that this conjecture is true by giving an explicit construction for the weight 1/2 mock theta functions, using some results found by Guerzhoy.## References

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## Bibliographic Information

**Sander Zwegers**- Affiliation: School of Mathematical Sciences, University College Dublin, Belfield, Dublin 4, Ireland
- Email: sander.zwegers@ucd.ie
- Received by editor(s): June 30, 2008
- Received by editor(s) in revised form: July 2, 2008
- Published electronically: November 18, 2008
- Communicated by: Ken Ono
- © Copyright 2008
American Mathematical Society

The copyright for this article reverts to public domain 28 years after publication. - Journal: Proc. Amer. Math. Soc.
**137**(2009), 1579-1584 - MSC (2000): Primary 11F11, 11F27
- DOI: https://doi.org/10.1090/S0002-9939-08-09684-6
- MathSciNet review: 2470815