A **cusp-index** of degree $d$ is a weakly increasing
list of positive integers $[u_1,\dots,u_k]$ with $\sum_{i=1}^k \phi(u_i) = d$.

Hypergeometric families $H(A,B)$ are indexed by pairs $(A,B)$ of cusp-indices of a common degree having no common entries.

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- Review status: beta
- Last edited by John Voight on 2019-08-23 16:53:17

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