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A058160 Triangle: Labeled commutative monoids of order n with k idempotents with a fixed identity. 3
1, 1, 1, 1, 6, 2, 4, 45, 36, 9, 6, 408, 648, 348, 76, 60, 7195, 13500, 11790, 5280, 1065, 120, 200016, 369930, 425280, 293640, 118890, 22566, 1920 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..29.

Index entries for sequences related to monoids

EXAMPLE

1; 1,1; 1,6,2; 4,45,36,9; 6,408,648,348,76; ...

CROSSREFS

a(n, k)=A058159(n, k)/n. Row sums give A058156. Column 1: A058162. Main diagonal A058164.

Sequence in context: A123139 A027599 A248272 * A033939 A021020 A215578

Adjacent sequences:  A058157 A058158 A058159 * A058161 A058162 A058163

KEYWORD

nonn,tabl,more

AUTHOR

Christian G. Bower, Nov 14 2000

STATUS

approved

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Last modified February 18 17:08 EST 2018. Contains 299325 sequences. (Running on oeis4.)