A079172 Number of non-associative closed binary operations on a set of order n.

0, 8, 19570, 4294963804, 298023223876769393, 10314424798490535546154887938, 256923577521058878088611477224227878265543, 6277101735386680763835789423207666416102355296268686994710, 196627050475552913618075908526912116283103450944214766927276968172610579252347

Offset

1,2

Comments

Each a(n) is equal to the sum of the products of each element in row n of A079174 and the corresponding element of A079210.

Links

Table of n, a(n) for n=1..9.

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

Index entries for sequences related to groupoids

Formula

a(n) = A002489(n) - A023814(n).

Crossrefs

Cf. A023814, A079173, A079174.

Sequence in context: A079597 A160743 A079182 * A173543 A067074 A220942

Adjacent sequences: A079169 A079170 A079171 * A079173 A079174 A079175

Keyword

nonn

Author

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

Extensions

More terms from Christian G. Bower, Nov 26 2003

More terms from Jinyuan Wang, Mar 02 2020

Status

approved