A113049 Triangle of sums of Jacobsthal numbers related to binomial(4n,n)/(3n+1) mod 4.

3, 11, 13, 43, 45, 53, 171, 173, 181, 213, 683, 685, 693, 725, 853, 2731, 2733, 2741, 2773, 2901, 3413, 10923, 10925, 10933, 10965, 11093, 11605, 13653, 43691, 43693, 43701, 43733, 43861, 44373, 46421, 54613, 174763, 174765, 174773, 174805, 174933

Offset: 0

Author

Paul Barry, Oct 11 2005

Keywords

• easy
• nonn
• tabl

Comments

First column is A007583(n+1). Main diagonal is A072197. Conjecture: A113048(n)=2 only if n=T(i,j).

Examples

			Rows begin
3;
11, 13;
43, 45, 53;
171, 173, 181, 213;
683, 685, 693, 725, 683;
2731,2733, 2741, 2773, 2901, 3413;
		

Formula

T(n, k)=if(k<=n, J(2n+3)+2J(2k), 0), J(n)=A001045(n).