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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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

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%I A221145 #11 Oct 28 2024 15:57:11
%S A221145 1,0,0,8,30,144,1120,9120,80892,808640,8908416,106889760,1389405160,
%T A221145 19452003648,291782125440,4668506495744,79364583206160,
%U A221145 1428562661736960,27142690917071872,542853814698737280,11399930105272855776,250798462399704792320
%N A221145 a(n) is the number of permutations of n elements with exactly one fixed point and no transpositions.
%F A221145 Equals n*A038205(n-1). - _Giovanni Resta_, Nov 13 2012
%e A221145 For n = 4 the a(4) = 8 solutions are (123), (124), (132), (134), (142), (143), (234), (243)
%Y A221145 Cf. A038205.
%Y A221145 Column k=1 of A344901.
%K A221145 nonn
%O A221145 1,4
%A A221145 _James Mahoney_, Nov 13 2012
%E A221145 Edited by _N. J. A. Sloane_, Jan 03 2013