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A318986
Number of loops of order n that are not groups.
0
0, 0, 0, 0, 0, 5, 107, 23745, 106228844, 9365022303538, 20890436195945769615, 1478157455158044452849321015
OFFSET
0,6
COMMENTS
A loop is a quasigroup with an identity element. - Muniru A Asiru, Dec 13 2018
LINKS
A. Hulpke, Petteri Kaski and Patric R. J. Östergård, The number of Latin squares of order 11, Math. Comp. 80 (2011) 1197-1219.
Brendan D. McKay, A. Meynert and W. Myrvold, Small Latin Squares, Quasigroups and Loops, J. Combin. Designs 15 (2007), no. 2, 98-119.
Wikipedia, Quasigroup
FORMULA
a(n) = A057771(n) - A000001(n).
CROSSREFS
Sequence in context: A355955 A113056 A336436 * A220549 A210904 A306990
KEYWORD
nonn,more
AUTHOR
Steve Szabo, Sep 06 2018
EXTENSIONS
a(7)-a(11) from Muniru A Asiru, Dec 07 2018
a(0) prepended by Jianing Song, Oct 26 2019
STATUS
approved