A058130 - OEIS

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A058130

Number of asymmetric monoids (semigroups with identity) of order n.

3

1, 2, 4, 19, 128, 1344, 20997, 1479686

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..8.

Index entries for sequences related to monoids

CROSSREFS

a(n)=A058136(n)*2-A058135(n).

Sequence in context: A272988 A168246 A212923 * A191563 A046082 A048774

Adjacent sequences: A058127 A058128 A058129 * A058131 A058132 A058133

KEYWORD

nonn,hard

AUTHOR

Christian G. Bower, Nov 13 2000

EXTENSIONS

a(8) from Christian G. Bower, Dec 26 2006

STATUS

approved

NODES