OFFSET
2,2
COMMENTS
LINKS
G. C. Greubel, Table of n, a(n) for n = 2..1000
Index entries for linear recurrences with constant coefficients, signature (-5,-10,-10,-5,-1).
FORMULA
a(n) = -5*a(n-1) -10*a(n-2) -10*a(n-3) -5*a(n-4) -a(n-5).
G.f.: x^2*(1+3*x)/(1+x)^5.
E.g.f.: x^2*(6 + 2*x - x^2)*exp(-x)/12. - G. C. Greubel, May 19 2019
MATHEMATICA
Table[(-1)^(n+1)*(n+1)*n*(n-1)*(n-4)/12, {n, 2, 40}] (* G. C. Greubel, Jun 12 2016 *)
LinearRecurrence[{-5, -10, -10, -5, -1}, {1, -2, 0, 10, -35}, 40] (* Vincenzo Librandi, Jun 13 2016 *)
PROG
(Magma) [(-1)^(n+1)*n*(n-1)*(n-4)*(n+1)/12: n in [2..40]]; // Vincenzo Librandi, Jun 13 2016
(PARI) vector(40, n, n++; (-1)^(n+1)*(n-4)*binomial(n+1, 3)/2) \\ G. C. Greubel, May 19 2019
(Sage) [(-1)^(n+1)*(n-4)*binomial(n+1, 3)/2 for n in (2..40)] # G. C. Greubel, May 19 2019
(GAP) List([2..40], n-> (-1)^(n+1)*(n-4)*Binomial(n+1, 3)/2) # G. C. Greubel, May 19 2019
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Jamel Ghanouchi, Nov 02 2009
STATUS
approved