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 1-3 of 3 results.

A090741 Maximum number of transversals in a Latin square of order n.

Original entry on oeis.org

1, 0, 3, 8, 15, 32, 133, 384, 2241
Offset: 1

Views

Author

Richard Bean, Feb 03 2004

Keywords

Comments

a(10) >= 5504 from Parker.
a(n) >= the number of transversals in a cyclic Latin square of the same order which for odd n is given by A006717((n-1)/2). - Eduard I. Vatutin, Nov 04 2020

Examples

			a(1), a(3), a(5), a(7) are from the group tables for Z_1, Z_3, Z_5 and Z_7 (see sequence A006717); a(4) and a(8) are from Z_2 x Z_2 and the non-cyclic groups of order 8 (see Bedford).
a(9) = 2241 from Z_3 x Z_3.
		

References

  • J. W. Brown, F. Cherry, L. Most, M. Most, E. T. Parker, W. D. Wallis, Completion of the spectrum of orthogonal diagonal Latin squares, Lecture notes in pure and applied mathematics. 1992. Vol. 139. pp. 43-49.
  • E. T. Parker, Computer investigations of orthogonal Latin squares of order 10, Proc. Sympos. Appl. Math., volume 15 (1963), 73-81.

Crossrefs

Formula

a(n) is asymptotically in between 3.2^n and 0.62^n n!. [McKay, McLeod, Wanless], [Cavenagh, Wanless]. - Ian Wanless, Jul 30 2010

Extensions

a(9) = 2241 from Brendan McKay and Ian Wanless, May 23 2004

A091326 Total number of inequivalent even binary linear codes of length n and any dimension k = 0, 1, ..., n-1.

Original entry on oeis.org

1, 2, 3, 6, 9, 18, 31, 64, 123
Offset: 1

Views

Author

N. J. A. Sloane, Mar 01 2004

Keywords

Comments

"Even" means that every word has even weight. Equivalently, the all-ones vector is in the dual code.

Crossrefs

Row sums of A091325.

A091327 Triangle T(n,k) read by rows giving number of inequivalent even binary linear [n,k] codes containing no zero columns (n >= 2, 1 <= k <= n-1).

Original entry on oeis.org

1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 2, 3, 2, 1, 0, 2, 4, 4, 2, 1, 1, 3, 8, 10, 7, 3, 1, 0, 3, 9, 18, 16, 9, 3, 1
Offset: 2

Views

Author

N. J. A. Sloane, Mar 01 2004

Keywords

Comments

"Even" means that every word has even weight. Equivalently, the all-ones vector is in the dual code.
Difference between successive rows of A091325.

Examples

			Triangle begins
1
0 1
1 1 1
0 1 1 1
1 2 3 2 1
0 2 4 4 2 1
		

Crossrefs

Cf. A091325. Row sums give A091328.
Showing 1-3 of 3 results.