A145120 Numbers X such that (X^2-19)/57 is a square.
38, 11438, 3454238, 1043168438, 315033414038, 95139047871038, 28731677423639438, 8676871442891239238, 2620386444075730610438, 791348029239427753113038, 238984484443863105709527038
Offset: 1
Examples
a(1)=38 because 38^2 = 57*25+19.
Links
- Index entries for linear recurrences with constant coefficients, signature (302,-1).
Programs
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Mathematica
LinearRecurrence[{302,-1},{38,11438},20] (* Harvey P. Dale, Jan 24 2013 *)
Formula
a(n) = 302*a(n-1) - a(n-2).
From R. J. Mathar, Nov 27 2011: (Start)
G.f.: -38*x*(-1+x) / ( 1-302*x+x^2 ).
a(n) = 38*A145123(n). (End)