OFFSET
0,2
LINKS
Colin Barker, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (0,50,0,-49).
FORMULA
a(n) = (7^n - 1)/(2^(4 - 3*(n mod 2))).
a(n) = 50*a(n-2)-49*a(n-4). - Colin Barker, Nov 06 2014
G.f.: 3*x*(7*x^2+x+1) / ((x-1)*(x+1)*(7*x-1)*(7*x+1)). - Colin Barker, Nov 06 2014
MATHEMATICA
a[n_] := (7^n - 1)/(2^(4 - 3*Mod[n, 2]));
Table[a[n], {n, 0, 30}]
PROG
(PARI) concat(0, Vec(3*x*(7*x^2+x+1)/((x-1)*(x+1)*(7*x-1)*(7*x+1)) + O(x^100))) \\ Colin Barker, Nov 06 2014
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Roger L. Bagula, Dec 03 2008
STATUS
approved