The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A079242

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A079242

Number of associative non-commutative non-anti-associative anti-commutative closed binary operations on a set of order n.
(history; published version)

#12 by Michael De Vlieger at Thu Jan 27 15:42:14 EST 2022

STATUS

proposed

approved

#11 by Andrew Howroyd at Thu Jan 27 14:33:51 EST 2022

STATUS

editing

proposed

#10 by Andrew Howroyd at Thu Jan 27 13:26:04 EST 2022

DATA

0, 0, 2, 2, 8, 2, 122, 2, 1682

OFFSET

1,2

0,3

COMMENTS

A079230(n)+A079232(n)+A079234(n)+A079236(n)+A079195(n)+A079240(n)+A079242(n)+A079244(n)+A063524(n)=A002489(n)

Each a(n) is equal to the sum of the products of each element in row n of A079208 and the corresponding element of A079210.

FORMULA

A079230(n) + A079232(n) + A079234(n) + A079236(n) + A079195(n) + A079240(n) + a(n) + A079244(n) + A063524(n) = A002489(n).

a(n) = Sum_{k>=1} A079208(n,k)*A079210(n,k).

CROSSREFS

Cf. A079208, A079243, (isomorphism classes), A079230, A079232, A079234, A079236, A079195, A079240, A079244, A063524.

EXTENSIONS

a(0)=0 prepended and terms a(5)-a(8) added by Andrew Howroyd, Jan 27 2022

STATUS

approved

editing

#9 by Charles R Greathouse IV at Tue Nov 05 02:36:15 EST 2013

STATUS

proposed

approved

#8 by Jon E. Schoenfield at Tue Nov 05 00:12:06 EST 2013

STATUS

editing

proposed

#7 by Jon E. Schoenfield at Tue Nov 05 00:12:04 EST 2013

KEYWORD

nonn,bref,more

STATUS

approved

editing

#6 by Russ Cox at Sun Jul 10 18:22:18 EDT 2011

LINKS

<a href="/Sindx_index/Se.html#semigroups">Index entries for sequences related to semigroups</a>

Discussion

Sun Jul 10

18:22

OEIS Server: https://oeis.org/edit/global/81

#5 by N. J. A. Sloane at Thu Nov 11 07:34:06 EST 2010

LINKS

<a href="/Sindx_Se.html#semigroups">Index entries for sequences related to semigroups</a>

KEYWORD

nonn,bref,more,new

#4 by N. J. A. Sloane at Fri Feb 27 03:00:00 EST 2009

LINKS

<a href="http://www.research.att.com/~njas/sequences/Sindx_Se.html#semigroups">Index entries for sequences related to semigroups</a>

KEYWORD

nonn,bref,more,new

#3 by N. J. A. Sloane at Tue Jan 24 03:00:00 EST 2006

KEYWORD

nonn,bref,more,new

AUTHOR

Christian van den Bosch (cjvdb1cjb(AT)student.cs.ucccjb.ie), Jan 03 2003