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A058115 Number of asymmetric idempotent semigroups of order n. 2
1, 1, 1, 3, 12, 68, 502, 4158 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

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

Index entries for sequences related to semigroups

CROSSREFS

Main diagonal of A058113.

Sequence in context: A039750 A296979 A004127 * A101313 A257605 A265886

Adjacent sequences:  A058112 A058113 A058114 * A058116 A058117 A058118

KEYWORD

nonn,hard

AUTHOR

Christian G. Bower, Nov 09 2000

EXTENSIONS

Updated Feb 19 2001

STATUS

approved

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Last modified October 22 20:57 EDT 2018. Contains 316502 sequences. (Running on oeis4.)