OFFSET
0,2
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..200
Index entries for linear recurrences with constant coefficients, signature (0,98,0,-1).
FORMULA
G.f.: (1 +4*x -x^2)/(x^4 -98*x^2 +1). - Vincenzo Librandi, Dec 14 2013
a(n) = 98*a(n-2) - a(n-4). - Vincenzo Librandi, Dec 14 2013
MATHEMATICA
Denominator[Convergents[Sqrt[150], 30]] (* or *) CoefficientList[Series[(1 + 4 x - x^2)/(x^4 - 98 x^2 + 1), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 14 2013 *)
PROG
(Magma) I:=[1, 4, 97, 392]; [n le 4 select I[n] else 98*Self(n-2)-Self(n-4): n in [1..40]]; // Vincenzo Librandi, Dec 14 2013
CROSSREFS
KEYWORD
nonn,frac,easy
AUTHOR
STATUS
approved