A003110 a(n) = number of special odd permutations of 2*n+1.

0, 2, 2, 108, 2028, 32870, 1213110, 46493784, 2310521000, 137466038346, 9842687925450, 832295357128500

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• more

Comments

a(n) is the number of odd permutations, pi(0),...,pi(2*n), of 0,...,2*n such that pi(0) = 0 and p(k) = k + pi(k) (mod 2*n+1), k=0,...,2*n is also a permutation of 0,...,2*n. - Sean A. Irvine, Jan 31 2015

References

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

Links

• D. H. Lehmer, Some properties of circulants, J. Number Theory 5 (1973), 43-54.

Crossrefs

Cf. A003109 (special even permutations), A003110 (total).

Extensions

Name clarified and offset corrected by Sean A. Irvine, Jan 31 2015

a(8)-a(9) from Sean A. Irvine, Jan 31 2015

a(10)-a(12) from Vaclav Kotesovec, May 17 2019 (using the terms of A003111 and A003112)