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A058132 Number of self-converse monoids (semigroups with identity) of order n. 4
1, 2, 5, 19, 84, 509, 3901, 48957 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..8.

Index entries for sequences related to monoids

CROSSREFS

a(n)=A058133(n)*2-A058129(n).

Sequence in context: A179566 A107377 A286886 * A286071 A002851 A316700

Adjacent sequences:  A058129 A058130 A058131 * A058133 A058134 A058135

KEYWORD

nonn,more

AUTHOR

Christian G. Bower, Nov 13 2000

EXTENSIONS

a(8) from Max Alekseyev, Jul 13 2009

STATUS

approved

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Last modified December 16 07:12 EST 2018. Contains 318158 sequences. (Running on oeis4.)