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Number of groups of order n^2.
1

%I #27 May 14 2023 19:35:21

%S 0,1,2,2,14,2,14,2,267,15,16,2,197,2,12,6,56092,2,176,2,221,13,12,2,

%T 8681,15,16,504,172,2,150,2,49487367289,6,16,4,3609,2,12,13,10281,2,

%U 228,2,167,63,12,2,15756130,15,227,7,219,2,7199,15,8085,21,16,2,4484

%N Number of groups of order n^2.

%H David Burrell, <a href="https://doi.org/10.1080/00927872.2021.2006680">On the number of groups of order 1024</a>, Communications in Algebra, 2021, 1-3.

%H Max Horn, <a href="https://groups.quendi.de/">Numbers of isomorphism types of finite groups of given order</a>

%F a(n) = A000001(n^2). - _R. J. Mathar_, Feb 23 2017

%t Join[{0}, FiniteGroupCount[Range[45]^2]]

%o (Magma) D:=SmallGroupDatabase(); [0] cat [ NumberOfSmallGroups(D, n^2) : n in [1..31] ];

%Y Cf. A000001, A000679, A140987, A141323, A235388.

%K nonn

%O 0,3

%A _Vincenzo Librandi_, Feb 16 2017

%E a(32) corrected by _David Burrell_, Jun 07 2022

%E Terms a(46) and beyond from Max Horn's website added by _Andrey Zabolotskiy_, May 14 2023