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%I #10 Jul 13 2012 17:33:04
%S 1,2,10,6,36,186,24,168,1032,6936,120,960,6840,53040,462120,720,6480,
%T 52560,461520,4499280,48453840,5040,50400,458640,4495680,48449520,
%U 571404960,7321381200,40320,443520,4475520,48424320,571374720,7321345920
%N Array read by antidiagonals: T(m,n) = Sum(1<=i<=m) i * (2m+n-1-i)!
%C Index numbers (compare A055089) of permutations like (2,4,6,...,1,3,5...).
%H Tilman Piesk, <a href="/A211365/b211365.txt">Table of n, a(n) for n = 1..2016</a>
%H Tilman Piesk, <a href="http://en.wikiversity.org/wiki/Inversion_%28discrete_mathematics%29#arrays1">Arrays of permutations</a> (Wikiversity)
%e T(3,2) = Sum( 1 <= i <= 3 ) [ i * (7-i)! ]
%e = 1*(7-1)! + 2*(7-2)! + 3*(7-3)!
%e = 1*720 + 2*120 + 3*24
%e = 1032
%Y Cf. A055089.
%K nonn,tabl
%O 1,2
%A _Tilman Piesk_, Jun 22 2012
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