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.

A208656 Triangle T(n, k) = n*C(n,k) - C(n-1,k-1), 1 <= k <= n, read by rows.

Original entry on oeis.org

0, 3, 1, 8, 7, 2, 15, 21, 13, 3, 24, 46, 44, 21, 4, 35, 85, 110, 80, 31, 5, 48, 141, 230, 225, 132, 43, 6, 63, 217, 427, 525, 413, 203, 57, 7, 80, 316, 728, 1078, 1064, 700, 296, 73, 8, 99, 441, 1164, 2016, 2394, 1974, 1116, 414, 91, 9, 120, 595, 1770
Offset: 1

Views

Author

Clark Kimberling, Mar 01 2012

Keywords

Comments

Mirror of A208657.
col 1: A005563
col 2: A127736
top edge: A000027

Examples

			First five rows:
0
3....1
8....7....2
15...21...13...3
24...46...44...21...4
		

Crossrefs

Programs

  • Mathematica
    z = 12;
    f[n_, k_] := n*Binomial[n, k] - Binomial[n - 1, k - 1]
    t = Table[f[n, k], {n, 1, z}, {k, 1, n}];
    TableForm[t] (* A208656 as a triangle *)
    Flatten[t]   (* A208656 as a sequence *)
    r = Table[f[n, k], {n, 1, z}, {k, n, 1, -1}];
    TableForm[r] (* A208657 as a triangle *)
    Flatten[r]   (* A208657 as a sequence *)
    Table[Sum[f[n, k], {k, 1, n}], {n, 1, 3 z}](* A208658 *)

Extensions

Definition amended by Georg Fischer, Feb 01 2022