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%I #9 May 01 2013 21:13:46
%S 1,4,24,336,5520,203040,7025760,510370560,30163311360,3577017024000,
%T 319851801561600,55850407258060800,7021439018770176000,
%U 1692163531361176473600,284409062346887622144000,90395009213694143422464000,19571060809440210728706048000,7929132907666579072319471616000
%N n!*A062868(n).
%C Let p = (p1..pn) and q = (q1..qn) be two random permutations of (1..n); call the pair (p,q) balanced if the number of i with pi > qi is the same as the number of i with pi < qi. Then a(n) is the number of balanced pairs.
%Y Cf. A062868, A196688.
%K nonn
%O 1,2
%A Jan Lakota, Oct 04 2011
%E a(1)-a(6) computed by Jan Lakota; extended by _N. J. A. Sloane_, Oct 04 2011
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