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A058112 Idempotent semigroups of order n. 2
1, 1, 3, 10, 46, 251, 1682, 13213 (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 monoids

Index entries for sequences related to semigroups

CROSSREFS

Main diagonal of A058108.

Sequence in context: A121138 A074508 A143500 * A020008 A167999 A000849

Adjacent sequences:  A058109 A058110 A058111 * A058113 A058114 A058115

KEYWORD

nonn,hard

AUTHOR

Christian G. Bower, Nov 09 2000

EXTENSIONS

Updated Feb 19 2001

STATUS

approved

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Last modified October 17 03:15 EDT 2018. Contains 316275 sequences. (Running on oeis4.)