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A076019 Number of nonisomorphic commutative systems with n elements having with one binary operation satisfying the equation B(AB)=A (semisymmetric quasigroups). 0
1, 1, 2, 2, 1, 3, 3, 13, 12 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..9.

CROSSREFS

Cf. A076016-A076021.

Sequence in context: A167754 A011020 A181512 * A071453 A212306 A080242

Adjacent sequences:  A076016 A076017 A076018 * A076020 A076021 A076022

KEYWORD

nonn,hard,more

AUTHOR

Richard C. Schroeppel, Oct 29 2002

STATUS

approved

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Last modified October 1 17:45 EDT 2020. Contains 337444 sequences. (Running on oeis4.)