A030260 Number of nonisomorphic commutative groupoids with no idempotents.

1, 0, 1, 38, 13872, 83360520, 10203847031340, 31023254154131753920, 2765562268014305034000397632, 8332535835277886736134596954072281240, 960864308045670310058158724983067048253497223280

Offset

0,4

Links

Table of n, a(n) for n=0..10.

Index entries for sequences related to groupoids

Crossrefs

Cf. A001329, A001425, A038021.

Sequence in context: A355589 A145120 A183581 * A145122 A134182 A110017

Adjacent sequences: A030257 A030258 A030259 * A030261 A030262 A030263

Keyword

nonn

Author

Christian G. Bower, Feb 15 1998 and May 15 1998

Status

approved