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A079195 Number of non-associative commutative closed binary operations on a set of order n. 14
0, 2, 666, 1047436 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A079192(n)+A079195(n)+A079198(n)+A023815(n)=A002489(n).

Each a(n) is equal to the sum of the products of each element in row n of A079197 and the corresponding element of A079210.

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 groupoids

CROSSREFS

Cf. A023815, A079192, A079196, A079197, A079198.

Sequence in context: A046856 A156938 A285221 * A120123 A140014 A188698

Adjacent sequences:  A079192 A079193 A079194 * A079196 A079197 A079198

KEYWORD

nonn

AUTHOR

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

STATUS

approved

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Last modified August 19 19:25 EDT 2017. Contains 290821 sequences.