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A228580
y-values in the solution to the Pell equation x^2 - 106*y^2 = -1.
2
389, 24958279289, 1601325744926727089, 102741223129724767598123789, 6591887355607898719696172384139389, 422936165108312951120152699451198782333889, 27135627492838193399902655844465538200645732157289
OFFSET
1,1
COMMENTS
All terms are multiples of 389.
FORMULA
a(n) = 64160102*a(n-1)-a(n-2).
G.f.: -389*x*(x-1) / (x^2-64160102*x+1).
MATHEMATICA
LinearRecurrence[{64160102, -1}, {389, 24958279289}, 20] (* or *) With[ {c1= 32080051-3115890Sqrt[106], c2 =32080051+3115890Sqrt[106]}, Table[ (41234c1^n+ 4005Sqrt[106] c1^n+41234c2^n-4005Sqrt[106] c2^n)/212, {n, 10}]]//Simplify (* Harvey P. Dale, Mar 02 2019 *)
PROG
(PARI) Vec(-389*x*(x-1)/(x^2-64160102*x+1) + O(x^30))
CROSSREFS
Cf. A228579 gives the corresponding x-values.
Sequence in context: A299819 A299719 A300340 * A242182 A136153 A069477
KEYWORD
nonn,easy
AUTHOR
Colin Barker, Aug 26 2013
STATUS
approved