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A058169 Triangle: Number of asymmetric self-converse semigroups of order n with k idempotents. 0
1, 2, 1, 3, 5, 1, 9, 19, 14, 2, 52, 82, 88, 43, 6, 624, 470, 556, 410, 162, 24, 19027, 4444, 3771, 3501, 2088, 731, 110 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..28.

Index entries for sequences related to semigroups

EXAMPLE

1; 2,1; 3,5,1; 9,19,14,2; 52,82,88,43,6; ...

CROSSREFS

Row sums give A058106.

Sequence in context: A120852 A285490 A058168 * A178074 A002249 A157127

Adjacent sequences:  A058166 A058167 A058168 * A058170 A058171 A058172

KEYWORD

nonn,tabl,hard

AUTHOR

Christian G. Bower, Nov 19 2000

STATUS

approved

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Last modified November 13 19:25 EST 2018. Contains 317149 sequences. (Running on oeis4.)