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%I M3569 #27 Dec 14 2022 09:07:01
%S 1,1,0,4,20,144,630,5696,39366,366400,3634950,39066624,479163828,
%T 6226534272,87238701000,1315130458112,20922813624336,355586138666496,
%U 6402373841107998,121479626301440000
%N Number of permutations of length n with spread 0.
%C The spread of a permutation p is the sum of i*p(i) over 0 <= i < n, reduced modulo n. - _Rintaro Matsuo_, Nov 26 2022
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H Rintaro Matsuo, <a href="/A004204/b004204.txt">Table of n, a(n) for n = 1..40</a>
%H R. L. Graham, and D. H. Lehmer, <a href="https://doi.org/10.1017/S1446788700019339">On the Permanent of Schur's Matrix</a>, Jour. Australian Math. Soc. 21 no. 4 (series A) (1976), 487-497.
%H Rintaro Matsuo, <a href="https://github.com/windows-server-2003/OEIS_calculation/tree/master/contents/permutation_spread">Code used to calculate up to a(40)</a>
%o (PARI) a(n) = my(v=[1..n], nb=0); forperm(v, p, if (sum(i=1, n-1, Mod(i,n)*p[i]) == 0, nb++)); nb; \\ _Michel Marcus_, Nov 30 2022
%K nonn
%O 1,4
%A _N. J. A. Sloane_
%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), May 17 2007
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