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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..7.

Index entries for sequences related to semigroups

CROSSREFS

Cf. A001423.

Sequence in context: A121421 A108043 A058561 * A213139 A023879 A084565

Adjacent sequences:  A058104 A058105 A058106 * A058108 A058109 A058110

KEYWORD

nonn,hard

AUTHOR

Christian G. Bower, Nov 09 2000

EXTENSIONS

Updated Feb 19 2001

STATUS

approved

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Last modified October 15 08:45 EDT 2018. Contains 316210 sequences. (Running on oeis4.)