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A221145 a(n) is the number of permutations of n elements with exactly one fixed point and no transpositions. 1

%I

%S 1,0,0,8,30,144,1120,9120,80892,808640,8908416,106889760,1389405160,

%T 19452003648,291782125440,4668506495744,79364583206160,

%U 1428562661736960,27142690917071872,542853814698737280,11399930105272855776,250798462399704792320

%N a(n) is the number of permutations of n elements with exactly one fixed point and no transpositions.

%F Equals n*A038205(n-1). - _Giovanni Resta_, Nov 13 2012

%e For n = 4 the a(4) = 8 solutions are (123), (124), (132), (134), (142), (143), (234), (243)

%Y Cf. A038205.

%K nonn

%O 1,4

%A _James Mahoney_, Nov 13 2012

%E Edited by _N. J. A. Sloane_, Jan 03 2013

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Last modified October 6 03:14 EDT 2022. Contains 357261 sequences. (Running on oeis4.)