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A079183 Number of isomorphism classes of non-commutative closed binary operations (groupoids) on a set of order n. 4
0, 6, 3201, 178937984, 2483527282664925, 14325590003288422852104768, 50976900301814583996024242298024434780, 155682086691137947272042494203068030678979503481450216 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

A001425(n)+a(n)=A001329(n).

Each a(n) is equal to the sum of the elements in row n of A079184.

LINKS

C. van den Bosch, Closed binary operations on small sets

Index entries for sequences related to groupoids

CROSSREFS

Sequence in context: A187083 A114184 A093884 * A030245 A172955 A198706

Adjacent sequences:  A079180 A079181 A079182 * A079184 A079185 A079186

KEYWORD

nonn

AUTHOR

Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003

EXTENSIONS

Edited and extended by Christian G. Bower (bowerc(AT)usa.net), Dec 12 2003

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Last modified February 15 15:20 EST 2012. Contains 205823 sequences.