cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-6 of 6 results.

A057771 Number of loops (quasigroups with an identity element) of order n.

Original entry on oeis.org

0, 1, 1, 1, 2, 6, 109, 23746, 106228849, 9365022303540, 20890436195945769617, 1478157455158044452849321016
Offset: 0

Views

Author

Christian G. Bower, Nov 01 2000

Keywords

Crossrefs

Extensions

a(8) from Juergen Buntrock (jubu(AT)jubu.com), Nov 03 2003.
a(9)-a(10) (from the McKay-Meynert-Myrvold article) from Richard Bean, Feb 17 2004
a(11) from Petteri Kaski (petteri.kaski(AT)cs.helsinki.fi), Sep 18 2009
a(0) prepended by Jianing Song, Oct 26 2019

A057991 Number of quasigroups of order n.

Original entry on oeis.org

1, 1, 1, 5, 35, 1411, 1130531, 12198455835, 2697818331680661, 15224734061438247321497, 2750892211809150446995735533513, 19464657391668924966791023043937578299025
Offset: 0

Views

Author

Christian G. Bower, Nov 01 2000

Keywords

Crossrefs

Extensions

More terms (from the McKay-Meynert-Myrvold article) from Richard Bean, Feb 17 2004
a(11) from Petteri Kaski (petteri.kaski(AT)cs.helsinki.fi), Sep 18 2009

A057996 Number of self-converse loops (quasigroups with an identity element) of order n.

Original entry on oeis.org

0, 1, 1, 1, 2, 4, 35, 556, 64065
Offset: 0

Views

Author

Christian G. Bower, Nov 01 2000

Keywords

Comments

x*y is isomorphic to y*x.

Crossrefs

Extensions

a(8) from Juergen Buntrock (jubu(AT)eule.in-berlin.de), Nov 17 2003
Offset corrected and a(0) prepended by Jianing Song, Oct 26 2019

A057994 Number of asymmetric quasigroups of order n.

Original entry on oeis.org

1, 1, 1, 0, 16, 1303, 1127628
Offset: 0

Views

Author

Christian G. Bower, Nov 01 2000

Keywords

Crossrefs

A058171 Number of quasigroups of order n, considered to be equivalent when they are isomorphic or anti-isomorphic (by reversal of the operator).

Original entry on oeis.org

1, 1, 1, 4, 24, 746, 567207
Offset: 0

Views

Author

Christian G. Bower, Nov 20 2000

Keywords

Crossrefs

a(n)=(A057991(n)+A057993)/2.

A058178 Triangle: Self-converse quasigroups of order n with k idempotents.

Original entry on oeis.org

1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 3, 6, 2, 1, 1, 16, 34, 14, 11, 4, 2, 858, 1453, 854, 500, 174, 38, 6
Offset: 0

Views

Author

Christian G. Bower, Nov 20 2000

Keywords

Examples

			1; 0,1; 0,1,0; 1,1,0,1; 3,6,2,1,1; ...
		

Crossrefs

Row sums give A057993.
Showing 1-6 of 6 results.