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A058112
Number of isomorphism classes of idempotent semigroups of order n.
3
1, 1, 3, 10, 46, 251, 1682, 13213, 119826, 1228712
(list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
Table of n, a(n) for n=0..9.
Index entries for sequences related to monoids
Index entries for sequences related to semigroups
CROSSREFS
Main diagonal of A058108 and A058137.
Cf. A027851, A351730 (labeled).
Sequence in context: A371549 A074508 A143500 * A345132 A020008 A167999
Adjacent sequences: A058109 A058110 A058111 * A058113 A058114 A058115
KEYWORD
nonn,hard
AUTHOR
Christian G. Bower, Nov 09 2000
EXTENSIONS
Updated Feb 19 2001
a(8)-a(9) added by Andrew Howroyd, Feb 17 2022
STATUS
approved

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Last modified October 21 14:36 EDT 2024. Contains 376988 sequences.
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