0,2

Also the number of transversals of a cyclic latin square of order 2n+1 and the number of orthomorphisms of the cyclic group of order 2n+1. - Ian M. Wanless (wanless(AT)maths.ox.ac.uk), Oct 07 2001

Also the number of complete mappings of a cyclic group of order 2n+1; also (2n+1) times the number of "standard" complete mappings of cyclic group of order 2n+1. - Jieh Hsiang, D.Frank Hsu and Yuh Pyng Shieh (arping(AT)turing.csie.ntu.edu.tw), May 08 2002

See A003111 for further information.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

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.

D. Novakovic, (2000) Computation of the number of complete mappings for permutations. Cybernetics & System Analysis, No. 2, v. 36, pp. 244-247.

Yuh Pyng Shieh, Jieh Hsiang and D. Frank Hsu, On the enumeration of Abelian k-complete mappings, vol. 144 of Congressus Numerantium, 2000, pp. 67-88

Yuh Pyng Shieh, Partition Strategies for #P-complete problem with applications to enumerative combinatorics, PhD thesis, National Taiwan University, 2001

I. Vardi, Computational Recreations in Mathematica. Addison-Wesley, Redwood City, CA, 1991, p. 118.

Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics.

Every term is odd and if n=2 mod 3 then a(n) is divisible by 3. Also a(n) is asymptotically less than 0.62^n n!. [McKay, McLeod, Wanless]

Sequence in context: A074241 A117694 A108210 this_sequence A059861 A030539 A028362

Adjacent sequences: A006714 A006715 A006716 this_sequence A006718 A006719 A006720

nonn,nice

N. J. A. Sloane (njas(AT)research.att.com).

More terms from Jieh Hsiang, D. Frank Hsu and Yuh Pyng Shieh (arping(AT)turing.csie.ntu.edu.tw), May 08 2002

a(12) added from A003111 by N. J. A. Sloane (njas(AT)research.att.com), Mar 29 2007