OFFSET
1,1
LINKS
Colin Barker, Table of n, a(n) for n = 1..1000
Milan Janjic, Enumerative Formulas for Some Functions on Finite Sets
Index entries for linear recurrences with constant coefficients, signature (15,-85,225,-274,120).
FORMULA
a(n) = 8*5^n-16*4^n+14*3^n-6*2^n+1.
G.f.: -x*(120*x^4-242*x^3+197*x^2-58*x+7) / ((x-1)*(2*x-1)*(3*x-1)*(4*x-1)*(5*x-1)). - Colin Barker, Feb 22 2015
MAPLE
f:=n->8*5^n-16*4^n+14*3^n-6*2^n+1;
MATHEMATICA
LinearRecurrence[{15, -85, 225, -274, 120}, {7, 47, 307, 1943, 11827}, 30] (* Harvey P. Dale, Dec 31 2021 *)
PROG
(PARI) Vec(-x*(120*x^4-242*x^3+197*x^2-58*x+7) / ((x-1)*(2*x-1)*(3*x-1)*(4*x-1)*(5*x-1)) + O(x^100)) \\ Colin Barker, Feb 22 2015
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Aleksandar M. Janjic and Milan Janjic, Feb 08 2007
STATUS
approved