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%I #11 May 01 2013 21:13:46
%S 0,0,6,120,4440,157680,9187920,557665920,50759291520,4795586208000,
%T 636749560339200,86796062772249600,15877174512431232000,
%U 2953945462595410483200,712801595188655900928000,173684063741850454560768000,53471242848053479728254976000,16530628080065352033845256192000
%N ((n!)^2-A196687(n))/2.
%C Let p = (p1..pn) and q = (q1..qn) be two random permutations of (1..n); call the pair (p,q) positive if the number of i with pi > qi is greater than the number of i with pi < qi. Then a(n) is the number of positive pairs.
%Y Cf. A062868, A196687. Equals n!*A179567(n).
%K nonn
%O 1,3
%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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