A110321 A Jacobsthal number related number triangle.

1, 1, 1, 6, 2, 1, 30, 18, 3, 1, 264, 120, 36, 4, 1, 2520, 1320, 300, 60, 5, 1, 30960, 15120, 3960, 600, 90, 6, 1, 428400, 216720, 52920, 9240, 1050, 126, 7, 1, 6894720, 3427200, 866880, 141120, 18480, 1680, 168, 8, 1, 123742080, 62052480, 15422400, 2600640

Offset: 0

Author

Paul Barry, Jul 20 2005

Keywords

• easy
• nonn
• tabl

Examples

			Rows begin
  1;
  1,1;
  6,2,1;
  30,18,3,1;
  264,120,36,4,1;
  2520,1320,300,60,5,1;
  30960,15120,3960,600,90,6,1;
		

Crossrefs

Row sums are A110322.

Antidiagonal sums are A110323.

Inverse is A110324.

Formula

T(n,k) = n!*J(n-k+1)/k!, where J(n)=A001045(n).

Column k has e.g.f. (x^k/k!)/(1-x-2x^2).