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A058159 Triangle: Labeled commutative monoids of order n with k idempotents. 4
1, 2, 2, 3, 18, 6, 16, 180, 144, 36, 30, 2040, 3240, 1740, 380, 360, 43170, 81000, 70740, 31680, 6390, 840, 1400112, 2589510, 2976960, 2055480, 832230, 157962, 15360 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

Index entries for sequences related to monoids

EXAMPLE

1; 2,2; 3,18,6; 16,180,144,36; 30,2040,3240,1740,380; ...

CROSSREFS

a(n, k)=A058160(n, k)*n. Row sums give A058155. Column 1: A034382. Main diagonal: A055512.

Sequence in context: A035796 A049009 A101817 * A058157 A230504 A265806

Adjacent sequences:  A058156 A058157 A058158 * A058160 A058161 A058162

KEYWORD

nonn,tabl,more

AUTHOR

Christian G. Bower, Nov 14 2000

STATUS

approved

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Last modified June 25 08:27 EDT 2021. Contains 345453 sequences. (Running on oeis4.)