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A058148 Monoids of order n with 2 idempotents, considered to be equivalent when they are isomorphic or anti-isomorphic (by reversal of the operator). 1
1, 3, 9, 30, 175, 3333 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

LINKS

Table of n, a(n) for n=2..7.

Index entries for sequences related to monoids

CROSSREFS

Column 2 of A058147.

Sequence in context: A120018 A091353 A003604 * A031031 A034550 A018370

Adjacent sequences:  A058145 A058146 A058147 * A058149 A058150 A058151

KEYWORD

nonn,more

AUTHOR

Christian G. Bower, Nov 14 2000

STATUS

approved

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Last modified July 26 05:08 EDT 2014. Contains 244924 sequences.