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.

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A080249 Stirling-like number triangle defined by the sequence A000292=C(n+3,3).

Original entry on oeis.org

1, 1, 1, 1, 5, 1, 1, 21, 15, 1, 1, 85, 171, 35, 1, 1, 341, 1795, 871, 70, 1, 1, 1365, 18291, 19215, 3321, 126, 1, 1, 5461, 184275, 402591, 135450, 10377, 210, 1, 1, 21845, 1848211, 8236095, 5143341, 716562, 28017, 330, 1, 1, 87381, 18503955, 166570111, 188253030, 45270813, 3069990, 67617, 495, 1
Offset: 0

Views

Author

Paul Barry, Feb 17 2003

Keywords

Comments

Columns include A002450, A016225. The defining sequence A000292=C(n+3,3) is the sequence of partial sums of the defining sequence for number triangle A080248.

Examples

			Triangle begins:
1;
1,    1;
1,    5,      1;
1,   21,     15,      1;
1,   85,    171,     35,      1;
1,  341,   1795,    871,     70,     1;
1, 1365,  18291,  19215,   3321,   126,   1;
1, 5461, 184275, 402591, 135450, 10377, 210, 1;
For example, 171 = 21+10*15, 35 = 15+20*1.
		

Crossrefs

Formula

T(n,k) = T(n-1,k-1) + A000292(k)*T(n-1,k). Columns are generated by 1/product{k=0..n, 1-C(k+3,3)*x}.

A080250 Expansion of 1/((1-x)(1-4x)(1-10x)(1-20x)).

Original entry on oeis.org

1, 35, 871, 19215, 402591, 8236095, 166570111, 3349906175, 67183250431, 1345516627455, 26928850135551, 538762184167935, 10777095520297471, 215560428864815615, 4311393762242888191, 86229727095755178495
Offset: 0

Views

Author

Paul Barry, Feb 17 2003

Keywords

Comments

Column k=3 in number triangle A080249.

Crossrefs

Programs

  • Magma
    [(1350*20^n-950*10^n+114*4^n-1)/513: n in [0..20]]; // Vincenzo Librandi, Aug 05 2013
  • Mathematica
    CoefficientList[Series[1/((1-x)(1-4x)(1-10x)(1-20x)),{x,0,20}],x] (* or *) Table[(1350*20^n-950*10^n+114*4^n-1)/513,{n,0,20}] (* or *) LinearRecurrence[{35,-354,1120,-800},{1,35,871,19215},21] (* Harvey P. Dale, Apr 25 2011 *)

Formula

G.f.: 1/((1-x)*(1-4*x)*(1-10*x)*(1-20*x)).
a(n) = (1350*20^n-950*10^n+114*4^n-1)/513.
a(0)=1, a(1)=35, a(2)=871, a(3)=19215, a(n) = 35*a(n-1) -354*a(n-2) +1120*a(n-3) -800*a(n-4). - Harvey P. Dale, Apr 25 2011

Extensions

Corrected by T. D. Noe, Nov 08 2006
Showing 1-2 of 2 results.