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A090741
Maximum number of transversals in a Latin square of order n.
7
1, 0, 3, 8, 15, 32, 133, 384, 2241
OFFSET
1,3
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
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.
LINKS
D. Bedford, Transversals in the Cayley tables of the non-cyclic groups of order 8, European Journal of Combinatorics, volume 12 (1991), 455-458.
N. J. Cavenagh and I. M. Wanless, On the number of transversals in Cayley tables of cyclic groups, Disc. Appl. Math. 158 (2010), 136-146.
B. D. McKay, J. C. McLeod and I. M. Wanless, The number of transversals in a Latin square, Des. Codes Cryptogr., 40, (2006) 269-284.
V. N. Potapov, On the number of transversals in Latin squares, arxiv:1506.01577 [math.CO], 2015.
Eduard Vatutin, Alexey Belyshev, Natalia Nikitina, Maxim Manzuk, Alexander Albertian, Ilya Kurochkin, Alexander Kripachev, and Alexey Pykhtin, Diagonalization and Canonization of Latin Squares, Supercomputing, Russian Supercomputing Days (RuSCDays 2023) Rev. Selected Papers Part II, LCNS Vol. 14389, Springer, Cham, 48-61.
Ian M. Wanless, A Generalization of Transversals for Latin Squares, Electronic Journal of Combinatorics, volume 9, number 1 (2002), R12.
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
EXAMPLE
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.
CROSSREFS
Sequence in context: A309052 A328858 A277224 * A376764 A255835 A032234
KEYWORD
hard,more,nonn
AUTHOR
Richard Bean, Feb 03 2004
EXTENSIONS
a(9) = 2241 from Brendan McKay and Ian Wanless, May 23 2004
STATUS
approved