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Array read by antidiagonals: T(m,n) = Sum(1<=i<=m) ( n + 2(i-1) )!
1

%I #9 Jul 13 2012 17:35:42

%S 1,2,7,6,26,127,24,126,746,5167,120,744,5166,41066,368047,720,5160,

%T 41064,368046,3669866,40284847,5040,41040,368040,3669864,40284846,

%U 482671466,6267305647,40320,367920,3669840,40284840,482671464,6267305646

%N Array read by antidiagonals: T(m,n) = Sum(1<=i<=m) ( n + 2(i-1) )!

%C Index numbers (compare A055089) of rows of adjacent transpositions.

%H Tilman Piesk, <a href="/A211368/b211368.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#arrays2">Arrays of permutations</a> (Wikiversity)

%e T(3,2) = Sum( 1 <= i <= 3 ) [ ( 2 + 2(i-1) )! ]

%e = (2+0)! + (2+2)! + (2+4)!

%e = 2 + 24 + 720

%e = 746

%Y Cf. A055089.

%K nonn,tabl

%O 1,2

%A _Tilman Piesk_, Jul 07 2012