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A113049
Triangle of sums of Jacobsthal numbers related to binomial(4n,n)/(3n+1) mod 4.
1
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
0,1
COMMENTS
First column is A007583(n+1). Main diagonal is A072197. Conjecture: A113048(n)=2 only if n=T(i,j).
FORMULA
T(n, k)=if(k<=n, J(2n+3)+2J(2k), 0), J(n)=A001045(n).
EXAMPLE
Rows begin
3;
11, 13;
43, 45, 53;
171, 173, 181, 213;
683, 685, 693, 725, 683;
2731,2733, 2741, 2773, 2901, 3413;
CROSSREFS
Sequence in context: A168454 A181086 A274343 * A370425 A225097 A079665
KEYWORD
easy,nonn,tabl
AUTHOR
Paul Barry, Oct 11 2005
STATUS
approved