A130888 Triangle read by rows, A051731(n,k) dot (1, 3, 7, 15, ...) with like numbers of terms.
1, 1, 3, 1, 0, 7, 1, 3, 0, 15, 1, 0, 0, 0, 31, 1, 3, 7, 0, 0, 63, 1, 0, 0, 0, 0, 0, 127, 1, 3, 0, 15, 0, 0, 0, 255
Offset: 1
Examples
First few rows of the triangle: 1; 1, 3; 1, 0, 7; 1, 3, 0, 15; 1, 0, 0, 0, 31; 1, 3, 7, 0, 0, 63; ... Row 4 = (1, 3, 0, 15) = (1, 1, 0, 1) dot (1, 3, 7, 15); where (1, 1, 0, 1) = row 4 of A051731.
Formula
Triangle read by rows, dot product of each row of A051731 and the same number of terms in the series (1, 3, 7, 15, ...).
G.f.: Sum_{k>0} (2^k-1)*(x*y)^k/(1-x^k). - Vladeta Jovovic, Dec 02 2008
Comments