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A058107
Number of asymmetric semigroups of order n, considered to be equivalent when they are isomorphic or anti-isomorphic (by reversal of the operator).
2
1, 1, 3, 12, 78, 746, 10965, 746277
OFFSET
0,3
CROSSREFS
Cf. A001423.
Sequence in context: A108043 A377534 A058561 * A213139 A023879 A084565
KEYWORD
nonn,hard
AUTHOR
Christian G. Bower, Nov 09 2000
EXTENSIONS
Updated Feb 19 2001
STATUS
approved