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 A003110 a(n) = number of special odd permutations of 2*n+1. (Formerly M0393) 4
 0, 2, 2, 108, 2028, 32870, 1213110, 46493784, 2310521000, 137466038346, 9842687925450, 832295357128500 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 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). Sequence in context: A210467 A156524 A194027 * A100956 A304915 A216481 Adjacent sequences:  A003107 A003108 A003109 * A003111 A003112 A003113 KEYWORD nonn,more AUTHOR 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) STATUS approved

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Last modified May 26 08:39 EDT 2020. Contains 334620 sequences. (Running on oeis4.)