OFFSET
1,3
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..1000
D. Zvonkine, Home Page
D. Zvonkine, Counting ramified coverings and intersection theory on Hurwitz spaces II (local structure of Hurwitz spaces and combinatorial results), Moscow Mathematical Journal, vol. 7 (2007), no. 1, 135-162.
Index entries for linear recurrences with constant coefficients, signature (5,-10,10,-5,1).
FORMULA
O.g.f.: 9*x^3*(1+11*x+15*x^2)/(1-x)^5 . - R. J. Mathar, Feb 01 2008
MATHEMATICA
Table[(3/8)(n-1)(n-2)(27n^2-137n+180), {n, 40}] (* Harvey P. Dale, Mar 23 2011 *)
LinearRecurrence[{5, -10, 10, -5, 1}, {0, 0, 9, 144, 765} , 50] (* G. C. Greubel, May 30 2016 *)
PROG
(PARI) a(n)=3*(n-1)*(n-2)*(27*n^2-137*n+180)/8 \\ Charles R Greathouse IV, Oct 21 2022
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jan 30 2008
STATUS
approved