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.

A055864 Coefficient triangle for certain polynomials.

Original entry on oeis.org

1, 3, 2, 16, 12, 9, 125, 100, 80, 64, 1296, 1080, 900, 750, 625, 16807, 14406, 12348, 10584, 9072, 7776, 262144, 229376, 200704, 175616, 153664, 134456, 117649, 4782969, 4251528, 3779136, 3359232, 2985984, 2654208, 2359296, 2097152
Offset: 1

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Author

Wolfdieter Lang, Jun 20 2000

Keywords

Comments

The coefficients of the partner polynomials are found in triangle A055858.

Examples

			Fourth row polynomial (n=4): p(4,x) = 125+100*x+80*x^2+64*x^3.
Triangle begins:
        1;
        3,       2;
       16,      12,       9;
      125,     100,      80,      64;
     1296,    1080,     900,     750,     625;
    16807,   14406,   12348,   10584,    9072,    7776;
   262144,  229376,  200704,  175616,  153664,  134456,  117649;
  4782969, 4251528, 3779136, 3359232, 2985984, 2654208, 2359296, 2097152;
  ...
		

Crossrefs

Column sequences are: A000272(n+1), n >= 1, A055865, A055070, A055867, A055868 for m=1..5.
Main diagonal gives A000169.

Programs

  • Mathematica
    a[n_, m_] /; n < m = 0; a[n_, m_] := n^(m-1)*(n+1)^(n-m); Table[a[n, m], {n, 1, 8}, {m, 1, n}] // Flatten (* Jean-François Alcover, Jun 20 2013 *)

Formula

a(n, m)=0 if n= m >= 1;
E.g.f. for column m: A(m, x); A(1, x)=-(W(-x)/x+1); recursion: A(m, x) = A(m-1, x)-int(A(m-1, x), x)/x-(((m-1)^(m-1))/m)* (x^(m-1))/(m-1)!, m >= 2; W(x) principal branch of Lambert's function.