Higman’s PORC conjecture for groups of prime-power order
Establish that, for each fixed positive integer k, the number of isomorphism types of groups of order p^k is polynomial in p on each residue class.
References
For larger powers of $p$, asymptotic formulas exist, and Higman's PORC Conjecture claims that, for a fixed $k$, the number of groups of order $pk$ is a function of $p$ that is polynomial on residue classes.
— The number of groups of cubefree order
(2608.18815 - Dietrich et al., 19 Aug 2026) in Section 1, Introduction