A200659 Triangle T(n,k), read by rows, given by (1,2,2,3,3,4,4,5,5,6,6,...) DELTA (1,0,1,0,1,0,1,0,1,0,1,0,1,...) where DELTA is the operator defined in A084938.

1, 1, 1, 3, 4, 1, 13, 21, 9, 1, 71, 132, 76, 16, 1, 461, 955, 670, 200, 25, 1, 3447, 7782, 6309, 2374, 435, 36, 1, 29093, 70441, 63833, 28413, 6713, 833, 49, 1, 273343, 701352, 694500, 351512, 99868, 16240, 1456, 64, 1

Offset: 0

Author

Philippe Deléham, Nov 20 2011

Keywords

• nonn
• tabl

Examples

			Triangle begins :
1
1, 1
3, 4, 1
13, 21, 9, 1
71, 132, 76, 16, 1
461, 955, 670, 200, 25, 1
3447, 7782, 6309, 2374, 435, 36, 1
29093, 70441, 63833, 28413, 6713, 833, 49, 1
273343, 701352, 694500, 351512, 99868, 16240, 1456, 64, 1
		

Crossrefs

Cf. A111537, A111546, A111556, A167872

Formula

Sum_{k, 0<=k<=n} T(n,k)*x^k = A153881(n+1), A000007(n), A003319(n), A111537(n), A111546(n), A111556(n), A177354(n-1) for x = -2,-1,0,1,2,3,4 respectively.

Sum_ {k, 0<=k<=n} T(n,k)*x^(n-k) = A000012(n), A111537(n), A167872(n) for x = 0,1,2 respectively.

T(k+1,k)=(k+1)^2.