OFFSET
1,1
COMMENTS
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..10000
Vincenzo Librandi, X^2-AY^2=1
Index entries for linear recurrences with constant coefficients, signature (2,-1).
FORMULA
a(n) = 2*a(n-1) -a(n-2).
G.f: x*(2515920+6468330*x)/(x-1)^2.
MATHEMATICA
Table[8984250*n-6468330, {n, 30}]
PROG
(Magma) I:=[2515920, 11500170]; [n le 2 select I[n] else 2*Self(n-1)-Self(n-2): n in [1..30]];
(PARI) a(n) = 8984250*n-6468330.
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Mar 06 2009
STATUS
approved