OFFSET
0,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..200
Index entries for linear recurrences with constant coefficients, signature (0, 0, 0, 206, 0, 0, 0, -1).
FORMULA
G.f.: (25 +26*x +77*x^2 +103*x^3 +77*x^4 -26*x^5 +25*x^6 -x^7)/(1 -206*x^4 +x^8). - Vincenzo Librandi, Nov 20 2013
a(n) = 206*a(n-4) - a(n-8). - Vincenzo Librandi, Nov 18 2013
MATHEMATICA
Numerator[Convergents[Sqrt[663], 30]] (* Harvey P. Dale, Aug 21 2011 *)
CoefficientList[Series[(25 + 26 x + 77 x^2 + 103 x^3 + 77 x^4 - 26 x^5 + 25 x^6 - x^7)/(1 - 206 x^4 + x^8), {x, 0, 30}], x] (* Vincenzo Librandi, Nov 20 2013 *)
PROG
(Magma) I:=[25, 26, 77, 103, 5227, 5330, 15887, 21217]; [n le 8 select I[n] else 206*Self(n-4)-Self(n-8): n in [1..30]]; // Vincenzo Librandi, Nov 18 2013
CROSSREFS
KEYWORD
nonn,cofr,frac,easy
AUTHOR
STATUS
approved