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A079180 Number of isomorphism classes of anti-associative closed binary operations on a set of order n. 7
1, 2, 10, 17780 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A079177(n)+A079180(n)=A001329(n).

Each a(n) is equal to the sum of the elements in row n of A079181.

LINKS

Table of n, a(n) for n=1..4.

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

Index entries for sequences related to semigroups

Index entries for sequences related to groupoids

CROSSREFS

Cf. A079177, A079179, A079181.

Sequence in context: A155733 A080485 A125149 * A027735 A085698 A057095

Adjacent sequences:  A079177 A079178 A079179 * A079181 A079182 A079183

KEYWORD

nonn

AUTHOR

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

STATUS

approved

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Last modified January 16 15:53 EST 2019. Contains 319195 sequences. (Running on oeis4.)