OFFSET
0,2
COMMENTS
Column k=3 in number triangle A080249.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..300
Index entries for linear recurrences with constant coefficients, signature (35,-354,1120,-800).
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
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 *)
PROG
(Magma) [(1350*20^n-950*10^n+114*4^n-1)/513: n in [0..20]]; // Vincenzo Librandi, Aug 05 2013
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Feb 17 2003
EXTENSIONS
Corrected by T. D. Noe, Nov 08 2006
STATUS
approved