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Moonshine for Rudvalis's sporadic group II

John F. Duncan
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Abstract

In Part I we introduced the notion of enhanced vertex operator superalgebra, and constructed an example which is self-dual, has rank 28, and whose full symmetry group is a seven-fold cover of the sporadic simple group of Rudvalis. In this article we construct a second enhanced vertex operator superalgebra whose full automorphism group is a cyclic cover of the Rudvalis group. This new example is self-dual and has rank -28. As in Part I, we can compute all the McKay--Thompson series associated to the action of the Rudvalis group explicitly. We observe that these series, when considered together with those of Part I, satisfy a genus zero property.

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John F. Duncan. 2008-11-03. Moonshine for Rudvalis's sporadic group II. https://arxiv.org/abs/math/0611355

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