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.

A089463 Triangle, read by rows, of coefficients for the third iteration of the hyperbinomial transform.

Original entry on oeis.org

1, 3, 1, 15, 6, 1, 108, 45, 9, 1, 1029, 432, 90, 12, 1, 12288, 5145, 1080, 150, 15, 1, 177147, 73728, 15435, 2160, 225, 18, 1, 3000000, 1240029, 258048, 36015, 3780, 315, 21, 1, 58461513, 24000000, 4960116, 688128, 72030, 6048, 420, 24, 1, 1289945088
Offset: 0

Views

Author

Paul D. Hanna, Nov 05 2003

Keywords

Comments

Equals the matrix cube of A088956 when treated as a lower triangular matrix. The 3rd hyperbinomial transform of a sequence {b} is defined to be the sequence {d} given by d(n) = Sum_{k=0..n} T(n,k)*b(k), where T(n,k) = 3*(n-k+3)^(n-k-1)*C(n,k). Given a table in which the n-th row is the n-th binomial transform of the first row, then the 3rd hyperbinomial transform of any diagonal results in the 3rd diagonal lower in the table.

Examples

			Rows begin:
  {1},
  {3,1},
  {15,6,1},
  {108,45,9,1},
  {1029,432,90,12,1},
  {12288,5145,1080,150,15,1},
  {177147,73728,15435,2160,225,18,1},
  {3000000,1240029,258048,36015,3780,315,21,1},..
		

Crossrefs

Cf. A089464(row sums), A089465(diagonal), A089460, A088956.

Programs

  • Mathematica
    Flatten[Table[3(n-k+3)^(n-k-1) Binomial[n,k],{n,0,10},{k,0,n}]] (* Harvey P. Dale, Jun 26 2013 *)
  • PARI
    for(n=0,10, for(k=0,n, print1(3*(n-k+3)^(n-k-1)*binomial(n,k), ", "))) \\ G. C. Greubel, Nov 17 2017

Formula

T(n, k) = 3*(n-k+3)^(n-k-1)*C(n, k).
E.g.f.: exp(x*y)*(-LambertW(-y)/y)^3.
Note: (-LambertW(-y)/y)^3 = Sum_{n>=0} 3*(n+3)^(n-1)*y^n/n!.