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A079182 Number of non-commutative closed binary operations on a set of order n. 4
0, 8, 18954, 4293918720 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

A023813(n)+A079182(n)=A002489(n).

Each a(n) is equal to the sum of the products of each element in row n of A079184 and the corresponding element of A079210.

LINKS

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

Index entries for sequences related to groupoids

FORMULA

n^(n^2)-n^((n^2-n)/2)

CROSSREFS

Cf. A023813, A079178, A079180.

Sequence in context: A198404 A079597 A160743 * A079172 A173543 A067074

Adjacent sequences:  A079179 A079180 A079181 * A079183 A079184 A079185

KEYWORD

nonn

AUTHOR

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

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Last modified February 14 18:47 EST 2012. Contains 205663 sequences.