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A076021 Number of fully idempotent systems with n elements having with one binary operation satisfying the equation B(AB)=A (semisymmetric quasigroups). 5
1, 0, 1, 1, 0, 0, 4, 0, 20 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

LINKS

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

CROSSREFS

Cf. A076016-A076020.

Sequence in context: A058348 A184946 A085618 * A199933 A078630 A178671

Adjacent sequences:  A076018 A076019 A076020 * A076022 A076023 A076024

KEYWORD

nonn

AUTHOR

Richard Schroeppel , Oct 29 2002

STATUS

approved

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Last modified November 20 15:32 EST 2014. Contains 249751 sequences.