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a(n) = n^(n*(n-1)/2).
10

%I #21 Jul 07 2022 09:24:32

%S 1,1,2,27,4096,9765625,470184984576,558545864083284007,

%T 19342813113834066795298816,22528399544939174411840147874772641,

%U 1000000000000000000000000000000000000000000000,1890591424712781041871514584574319778449301246603238034051

%N a(n) = n^(n*(n-1)/2).

%C Labeled commutative idempotent groupoids.

%C Product of terms in n-th row of A076112.

%H Alois P. Heinz, <a href="/A076113/b076113.txt">Table of n, a(n) for n = 0..36</a>

%H <a href="/index/Gre#groupoids">Index entries for sequences related to groupoids</a>

%o (PARI) a(n) = n^(n*(n-1)/2); \\ _Joerg Arndt_, Nov 04 2013

%Y Cf. A000169, A002489, A006125, A023037, A030257, A076112, A090588.

%K easy,nonn

%O 0,3

%A _Amarnath Murthy_, Oct 09 2002

%E More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 20 2003

%E a(0)=1 prepended by _Alois P. Heinz_, Jun 30 2022