A211365 Array read by antidiagonals: T(m,n) = Sum(1<=i<=m) i * (2m+n-1-i)!

1, 2, 10, 6, 36, 186, 24, 168, 1032, 6936, 120, 960, 6840, 53040, 462120, 720, 6480, 52560, 461520, 4499280, 48453840, 5040, 50400, 458640, 4495680, 48449520, 571404960, 7321381200, 40320, 443520, 4475520, 48424320, 571374720, 7321345920

Offset: 1

Author

Tilman Piesk, Jun 22 2012

Keywords

• nonn
• tabl

Comments

Index numbers (compare A055089) of permutations like (2,4,6,...,1,3,5...).

Examples

			T(3,2) = Sum( 1 <= i <= 3 ) [ i * (7-i)! ]
= 1*(7-1)! + 2*(7-2)! + 3*(7-3)!
= 1*720 + 2*120 + 3*24
= 1032
		

Links

• Tilman Piesk, Table of n, a(n) for n = 1..2016
• Tilman Piesk, Arrays of permutations (Wikiversity)

Crossrefs

Cf. A055089.