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.

A056578 a(n) = 1 + 2*n + 3*n^2 + 4*n^3.

Original entry on oeis.org

1, 10, 49, 142, 313, 586, 985, 1534, 2257, 3178, 4321, 5710, 7369, 9322, 11593, 14206, 17185, 20554, 24337, 28558, 33241, 38410, 44089, 50302, 57073, 64426, 72385, 80974, 90217, 100138, 110761, 122110, 134209, 147082, 160753, 175246, 190585, 206794, 223897, 241918
Offset: 0

Views

Author

Henry Bottomley, Jun 29 2000

Keywords

Examples

			For n>4 this is 4321 translated from base n to base 10.
		

Crossrefs

Note: 1 + 2*x + 3*x^2 + 4*x^3 is the first derivative of 1 + x + x^2 + x^3 + x^4, i.e., A053699.

Programs

Formula

a(n) = (A053699(n+1) - A053699(n-1))/2 - 4*n - 1.
G.f.: (1 + 6*x + 15*x^2 + 2*x^3)/(1-x)^4. - Colin Barker, Jan 10 2012
From Elmo R. Oliveira, Apr 20 2025: (Start)
E.g.f.: exp(x)*(1 + 9*x + 15*x^2 + 4*x^3).
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4). (End)

Extensions

More terms from Elmo R. Oliveira, Apr 20 2025