%I A088436
%S A088436 0,1,3,6,30,225,1575,12180,109620,1100925,12110175,145259730,1888376490,
%T A088436 26438216805,396573252075,6345155817000,107867648889000,
%U A088436 1941617990136825,36890741812599675,737814829704702750
%N A088436 Number of permutations in the symmetric group S_n that have exactly one
transposition in their cycle decomposition.
%D A088436 Ch. A. Charalambides, Enumerative Combinatorics, Chapman & Hall/CRC,
Boca Raton, Florida, 2002, p. 189, Exercise 19 for k=1. With (-1)^k
omitted.
%F A088436 a(n)=n!*sum(((-1)^j)/(j!*2^j),j=0..floor(n/2)-k)/(k!*2^k), n>=1.
%F A088436 E.g.f.: x^2/(1-x)/2*exp(-x^2/2). - Vladeta Jovovic (vladeta(AT)eunet.rs),
Nov 09 2003
%Y A088436 Cf. A000266, A027616, A000240.
%Y A088436 Sequence in context: A090932 A157534 A133799 this_sequence A088506 A061137
A012280
%Y A088436 Adjacent sequences: A088433 A088434 A088435 this_sequence A088437 A088438
A088439
%K A088436 nonn
%O A088436 1,3
%A A088436 Yuval Dekel (dekelyuval(AT)hotmail.com), Nov 09 2003
%E A088436 More terms from Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de),
Feb 22 2008
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