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Number of permutations of length n with spread 1.
(Formerly M2753)
2

%I M2753 #25 Dec 15 2022 02:51:14

%S 1,3,8,25,108,735,4608,40824,362000,3628185,40766976,478988081,

%T 6227101888,87146087625,1300561920000,20922788404479,355737629952000,

%U 6402373698206889,121810906419200000,2432822933484213543,51090942172652090368,1124000727778962143055

%N Number of permutations of length n with spread 1.

%C The spread of a permutation p is Sum_{i=0..n-1} i*p(i), reduced modulo n. - _Rintaro Matsuo_, Dec 14 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="/A004205/b004205.txt">Table of n, a(n) for n = 2..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>

%K nonn

%O 2,2

%A _N. J. A. Sloane_

%E More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), May 17 2007