A058132 - OEIS

A058132

Number of self-converse monoids (semigroups with identity) of order n.

0, 1, 2, 5, 19, 84, 509, 3901, 48957 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`0,3`
	LINKS	`Table of n, a(n) for n=0..8.` `Index entries for sequences related to monoids`
	FORMULA	`a(n) = A058133(n)*2 - A058129(n).`
	CROSSREFS	`Cf. A058129, A058133.` `Sequence in context: A179566 A107377 A286886 * A286071 A002851 A324618` `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` `a(0) prepended by Jianing Song, Oct 26 2019`
	STATUS	`approved`

Last modified June 29 05:44 EDT 2022. Contains 354910 sequences. (Running on oeis4.)