A057771 Number of loops (quasigroups with an identity element) of order n.

0, 1, 1, 1, 2, 6, 109, 23746, 106228849, 9365022303540, 20890436195945769617, 1478157455158044452849321016

Offset: 0

Author

Christian G. Bower, Nov 01 2000

Keywords

• nonn
• more
• nice

Links

• Brendan D. McKay, A. Meynert and W. Myrvold, Small Latin Squares, Quasigroups and Loops, J. Combin. Designs 15 (2007), no. 2, 98-119.
• A. Hulpke, Petteri Kaski and Patric R. J. Östergård, The number of Latin squares of order 11, Math. Comp. 80 (2011) 1197-1219.
• Index entries for sequences related to quasigroups

Crossrefs

Cf. A000315, A057991, A057992, A057993, A057994, A057996, A057997, A057998, A089925.

Extensions

a(8) from Juergen Buntrock (jubu(AT)jubu.com), Nov 03 2003.

a(9)-a(10) (from the McKay-Meynert-Myrvold article) from Richard Bean, Feb 17 2004

a(11) from Petteri Kaski (petteri.kaski(AT)cs.helsinki.fi), Sep 18 2009

a(0) prepended by Jianing Song, Oct 26 2019