OFFSET
1,2
COMMENTS
The corresponding values of x of this Pell equation are in A174751.
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..200
Index entries for linear recurrences with constant coefficients, signature (50,-1).
FORMULA
a(n) = 50*a(n-1)-a(n-2) with a(1)=0, a(2)=4.
G.f.: 4*x^2/(1-50*x+x^2).
MATHEMATICA
LinearRecurrence[{50, -1}, {0, 4}, 30]
PROG
(Magma) I:=[0, 4]; [n le 2 select I[n] else 50*Self(n-1)-Self(n-2): n in [1..20]];
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Apr 15 2010
STATUS
approved