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A145695
Numbers X such that there exists Y in N with X^2=111*Y^2+37.
1
74, 43586, 25715666, 15172199354, 8951571903194, 5281412250685106, 3116024276332309346, 1838449041623811829034, 1084681818533772646820714, 639960434485884237812392226, 377575571664853166536664592626
OFFSET
1,1
FORMULA
a(n+2) = 590*a(n+1)-a(n).
G.f.: -74*x*(x-1) / (x^2-590*x+1). - Colin Barker, Oct 21 2014
EXAMPLE
a(1)=74 because the first relation is 74^2=111*7^2+37.
MATHEMATICA
CoefficientList[Series[74 (1 - x)/(x^2 - 590 x + 1), {x, 0, 20}], x] (* Vincenzo Librandi, Oct 21 2014 *)
PROG
(PARI) Vec(-74*x*(x-1)/(x^2-590*x+1) + O(x^20)) \\ Colin Barker, Oct 21 2014
(Magma) I:=[74, 43586]; [n le 2 select I[n] else 590*Self(n-1)-Self(n-2): n in [1..15]]; // Vincenzo Librandi, Oct 21 2014
CROSSREFS
Sequence in context: A268090 A278378 A324523 * A116132 A257534 A063680
KEYWORD
easy,nonn
AUTHOR
Richard Choulet, Oct 16 2008
EXTENSIONS
Editing and a(11) from Colin Barker, Oct 21 2014
STATUS
approved