A115381 Correlation triangle for Fredholm-Rueppel sequence A036987.

1, 1, 1, 0, 2, 0, 1, 1, 1, 1, 0, 1, 2, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 3, 1, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 3, 1, 0, 1, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 3, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 1, 3, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0

Offset: 0

Author

Paul Barry, Jan 21 2006

Keywords

• easy
• nonn
• tabl

Comments

Row sums are A115367. T(2n,n) is partial sums of squares of A036987(n).

Examples

			Triangle begins
1,
1, 1,
0, 2, 0,
1, 1, 1, 1,
0, 1, 2, 1, 0,
0, 1, 1, 1, 1, 0,
0, 0, 1, 3, 1, 0, 0,
1, 0, 1, 1, 1, 1, 0, 1,
0, 1, 0, 1, 3, 1, 0, 1, 0,
0, 1, 0, 1, 1, 1, 1, 0, 1, 0,
0, 0, 1, 1, 1, 3, 1, 1, 1, 0, 0,
0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0,
0, 0, 0, 1, 1, 1, 3, 1, 1, 1, 0, 0, 0,
0, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0,
0, 0, 0, 0, 1, 1, 1, 4, 1, 1, 1, 0, 0, 0, 0,
1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 1,
0, 1, 0, 0, 0, 1, 1, 1, 4, 1, 1, 1, 0, 0, 0, 1, 0
		

Formula

G.f.: A(x)A(x*y)/(1-x^2*y) where A(x)=sum{k>=0, x^(2^k-1)}. Number triangle T(n, k)=sum{j=0..n, if(j<=k, A036987(k-j), 0)*if(j<=(n-k), A036987(n-k-j), 0)}