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A041109
Denominators of continued fraction convergents to sqrt(62).
2
1, 1, 7, 8, 119, 127, 881, 1008, 14993, 16001, 110999, 127000, 1888999, 2015999, 13984993, 16000992, 237998881, 253999873, 1761998119, 2015997992, 29985970007, 32001967999, 221997778001, 253999746000, 3777994222001, 4031993968001, 27969958030007
OFFSET
0,3
FORMULA
G.f.: -(x^2-x-1)*(x^4+8*x^2+1) / (x^8-126*x^4+1). - Colin Barker, Nov 12 2013
a(n) = 126*a(n-4) - a(n-8). - Vincenzo Librandi, Dec 11 2013
MATHEMATICA
Denominator[Convergents[Sqrt[62], 30]] (* Vincenzo Librandi, Dec 11 2013 *)
LinearRecurrence[{0, 0, 0, 126, 0, 0, 0, -1}, {1, 1, 7, 8, 119, 127, 881, 1008}, 30] (* Harvey P. Dale, Oct 26 2016 *)
PROG
(Magma) I:=[1, 1, 7, 8, 119, 127, 881, 1008]; [n le 8 select I[n] else 126*Self(n-4)-Self(n-8): n in [1..40]]; // Vincenzo Librandi, Dec 11 2013
CROSSREFS
KEYWORD
nonn,cofr,easy,frac
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 12 2013
STATUS
approved