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A079205 Number of isomorphism classes of non-associative non-commutative anti-associative anti-commutative closed binary operations on a set of order n, listed by class size. 9
0, 2, 0, 0, 2, 0, 0, 0, 0, 2, 0, 29, 0, 237, 4374 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A079202(n)+A079203(n)+A079204(n)+A079205(n)+A079197(n)+A079207(n)+A079208(n)+A079209(n)+A063524(n)=A079171(n)

Elements per row: 1,2,4,8,16,30,... (given by A027423, number of positive divisors of n!)

First four rows: 0; 2,0; 0,2,0,0; 0,0,2,0,29,0,237,4374

A079236(x) is equal to the sum of the products of each element in row x of this sequence and the corresponding element of A079210.

The sum of each row x of this sequence is given by A079237(x).

LINKS

Table of n, a(n) for n=1..15.

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

Index entries for sequences related to groupoids

CROSSREFS

Cf. A079202, A079203, A079204, A079197, A079207, A079208, A079209, A079236, A079237.

Sequence in context: A033723 A138811 A107494 * A317641 A107497 A000095

Adjacent sequences:  A079202 A079203 A079204 * A079206 A079207 A079208

KEYWORD

nonn,tabf

AUTHOR

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

STATUS

approved

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Last modified April 23 21:25 EDT 2019. Contains 322388 sequences. (Running on oeis4.)