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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: A355050 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 August 10 16:24 EDT 2022. Contains 356039 sequences. (Running on oeis4.)