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.

A067402 Triangle with columns built from certain power sequences.

Original entry on oeis.org

1, 1, 1, 1, 3, 1, 1, 12, 5, 1, 1, 48, 45, 7, 1, 1, 192, 405, 112, 9, 1, 1, 768, 3645, 1792, 225, 11, 1, 1, 3072, 32805, 28672, 5625, 396, 13, 1, 1, 12288, 295245, 458752, 140625, 14256, 637, 15, 1, 1, 49152, 2657205, 7340032, 3515625, 513216, 31213, 960, 17, 1
Offset: 0

Views

Author

Wolfdieter Lang, Jan 25 2002

Keywords

Examples

			Triangle starts:
      m=0   1   2   3   4
  n=0:  1;
  n=1:  1,  1;
  n=2:  1,  3,  1;
  n=3:  1, 12,  5,  1;
  n=4:  1, 48, 45,  7,  1;
  ...
		

Crossrefs

Cf. A009998 (triangle built from powers of (m+1)).
Columns m=0..8: A000012, A002001, A067403-A067409.

Programs

  • Mathematica
    A[n_,m_]:=If[n==m,1,(2m+1)(m+1)^(2(n-m-1))]; Flatten[Table[A[n,m],{n,0,9},{m,0,n}]] (* Stefano Spezia, Sep 30 2022 *)

Formula

a(n, m) = 1 if n=m; a(n, m) = (2*m+1)*(m+1)^(2*(n-m-1)) if n>m>=0.
G.f. for column m: (x^m)*(1-x*m^2)/(1-x*(m+1)^2).

Extensions

More terms from Larry Reeves (larryr(AT)acm.org), Jun 11 2002