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.

A188475 a(n) = (2*n^3 + 3*n^2 + n + 3)/3.

Original entry on oeis.org

1, 3, 11, 29, 61, 111, 183, 281, 409, 571, 771, 1013, 1301, 1639, 2031, 2481, 2993, 3571, 4219, 4941, 5741, 6623, 7591, 8649, 9801, 11051, 12403, 13861, 15429, 17111, 18911, 20833, 22881, 25059, 27371, 29821, 32413, 35151, 38039, 41081, 44281, 47643
Offset: 0

Views

Author

Paul Barry, Apr 01 2011

Keywords

Comments

Hankel transform of A137398(n+1) (conjecture).

Programs

Formula

G.f.: (1 - x + 5*x^2 - x^3)/(1-x)^4.
a(n) = A006331(n) + 1. - Bruno Berselli, Nov 14 2011

A188474 A generalized Deutsch triangle.

Original entry on oeis.org

1, 1, 1, 1, 5, 1, 1, 10, 10, 1, 1, 16, 40, 16, 1, 1, 23, 102, 102, 23, 1, 1, 31, 209, 393, 209, 31, 1, 1, 40, 376, 1122, 1122, 376, 40, 1, 1, 50, 620, 2656, 4296, 2656, 620, 50, 1, 1, 61, 960, 5536, 13100, 13100, 5536, 960, 61, 1, 1, 73, 1417, 10522, 34036, 50180, 34036, 10522, 1417, 73, 1
Offset: 0

Views

Author

Paul Barry, Apr 01 2011

Keywords

Comments

Member r=2 of the family of "Pascal-like" triangles with 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)*r^(j-1)}.
The Deutsch triangle A100754 corresponds to r=1.
Row sums are A137398(n+1) (conjecture). Diagonal sums are A188476.

Examples

			Triangle begins
1,
1, 1,
1, 5, 1,
1, 10, 10, 1,
1, 16, 40, 16, 1,
1, 23, 102, 102, 23, 1,
1, 31, 209, 393, 209, 31, 1,
1, 40, 376, 1122, 1122, 376, 40, 1,
1, 50, 620, 2656, 4296, 2656, 620, 50, 1,
1, 61, 960, 5536, 13100, 13100, 5536, 960, 61, 1,
1, 73, 1417, 10522, 34036, 50180, 34036, 10522, 1417, 73, 1
		

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)*2^(j-1)}.
Showing 1-2 of 2 results.