OFFSET
0,3
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..200
Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,140452,0,0,0,0,0,0,0,0,0,-1).
FORMULA
G.f.: -(x^18 -x^17 +2*x^16 -5*x^15 +17*x^14 -260*x^13 +797*x^12 -1854*x^11 +2651*x^10 -4505*x^9 -2651*x^8 -1854*x^7 -797*x^6 -260*x^5 -17*x^4 -5*x^3 -2*x^2 -x -1) / (x^20 -140452*x^10 +1). - Colin Barker, Nov 18 2013
a(n) = 140452*a(n-10) - a(n-20) for n>19. - Vincenzo Librandi, Dec 18 2013
MATHEMATICA
Denominator[Convergents[Sqrt[243], 30]] (* Vincenzo Librandi, Dec 18 2013 *)
PROG
(Magma) I:=[1, 1, 2, 5, 17, 260, 797, 1854, 2651, 4505, 137801, 142306, 280107, 702520, 2387667, 36517525, 111940242, 260398009, 372338251, 632736260]; [n le 20 select I[n] else 140452*Self(n-10)-Self(n-20): n in [1..40]]; // Vincenzo Librandi, Dec 18 2013
CROSSREFS
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 18 2013
STATUS
approved