OFFSET
0,2
COMMENTS
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (25,-250,1250,-3125,3125).
FORMULA
a(n) = 5^n*(n^4 + 74*n^3 + 1571*n^2 + 10354*n + 15000)/15000.
G.f.: (1 - 4*x)^4/(1 - 5*x)^5.
E.g.f.: (24 + 96*x + 72*x^2 + 16*x^3 + x^4)*exp(5*x)/24. - G. C. Greubel, Oct 18 2018
MATHEMATICA
LinearRecurrence[{25, -250, 1250, -3125, 3125}, {1, 9, 71, 519, 3606}, 50] (* G. C. Greubel, Oct 18 2018 *)
PROG
(PARI) x='x+O('x^30); Vec((1-4*x)^4/(1-5*x)^5) \\ G. C. Greubel, Oct 18 2018
(Magma) m:=30; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!((1-4*x)^4/(1-5*x)^5)); // G. C. Greubel, Oct 18 2018
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paul Barry, Mar 31 2003
STATUS
approved