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A058147
Triangle read by rows: number of monoids of order n with k idempotents, considered to be equivalent when they are isomorphic or anti-isomorphic (by reversal of the operator).
2
1, 1, 1, 1, 3, 2, 2, 9, 10, 6, 1, 30, 47, 52, 26, 2, 175, 283, 413, 365, 135, 1, 3333, 2139, 3630, 4597, 3155, 875, 5
OFFSET
1,5
EXAMPLE
1; 1,1; 1,3,2; 2,9,10,6; 1,30,47,52,26; ...
CROSSREFS
Row sums give A058133. Main diagonal: A002788(n-1). Columns 1-3: A000001, A058148, A058149.
Sequence in context: A177460 A091015 A256097 * A193344 A119954 A100804
KEYWORD
nonn,tabl,more
AUTHOR
Christian G. Bower, Nov 14 2000
STATUS
approved