cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-2 of 2 results.

A188476 Diagonal sums of number triangle A188474.

Original entry on oeis.org

1, 1, 2, 6, 12, 27, 65, 150, 353, 843, 2014, 4843, 11713, 28433, 69292, 169470, 415754, 1022868, 2523120, 6238645, 15459561, 38387191, 95497612, 237989801, 594062697, 1485141397, 3718116380, 9320941698, 23396109986, 58795356627, 147920737819
Offset: 0

Views

Author

Paul Barry, Apr 01 2011

Keywords

Comments

Hankel transform is A188477(n+1).

Formula

a(n)=sum{k=0..floor(n/2), sum{j=0..n-2k+1, (j/(n-k+2-j))*C(n-k+2-j,n-k+1)*C(n-k+2-j,k+1)*2^(j-1)}}.
Conjecture: (n+3)*a(n) +(-4*n-9)*a(n-1) +n*a(n-2) -3*a(n-3) +3*(5*n+1)*a(n-4) +6*(n)*a(n-5) +6*(n-1)*a(n-6) +4*(-n+3)*a(n-7)=0. - R. J. Mathar, Dec 03 2014

A188461 A Deutsch-Fibonacci triangle.

Original entry on oeis.org

1, 1, 1, 1, 5, 1, 1, 10, 10, 1, 1, 16, 39, 16, 1, 1, 23, 99, 99, 23, 1, 1, 31, 203, 375, 203, 31, 1, 1, 40, 366, 1065, 1065, 366, 40, 1, 1, 50, 605, 2521, 4027, 2521, 605, 50, 1, 1, 61, 939, 5266, 12220, 12220, 5266, 939, 61, 1
Offset: 0

Views

Author

Paul Barry, Apr 01 2011

Keywords

Comments

Second column is A052905. Third column is A188480.

Examples

			Triangle begins
1,
1, 1,
1, 5, 1,
1, 10, 10, 1,
1, 16, 39, 16, 1,
1, 23, 99, 99, 23, 1,
1, 31, 203, 375, 203, 31, 1,
1, 40, 366, 1065, 1065, 366, 40, 1,
1, 50, 605, 2521, 4027, 2521, 605, 50, 1,
1, 61, 939, 5266, 12220, 12220, 5266, 939, 61, 1
		

Crossrefs

Formula

T(n,k)=sum{j=0..n-k+1, (j/(n+2-j))C(n+2-j,n-k+1)*C(n+2-j,k+1)*F(j+1)}.
Showing 1-2 of 2 results.