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A041237
Denominators of continued fraction convergents to sqrt(130).
3
1, 2, 5, 112, 229, 570, 12769, 26108, 64985, 1455778, 2976541, 7408860, 165971461, 339351782, 844675025, 18922202332, 38689079689, 96300361710, 2157297037309, 4410894436328, 10979085909965, 245950784455558, 502880654821081, 1251712094097720
OFFSET
0,2
FORMULA
G.f.: -(x^4-2*x^3+5*x^2+2*x+1) / (x^6+114*x^3-1). - Colin Barker, Nov 14 2013
a(n) = 114*a(n-3) + a(n-6). - Vincenzo Librandi, Dec 13 2013
MATHEMATICA
Denominator[Convergents[Sqrt[130], 30]] (* Vincenzo Librandi, Dec 13 2013 *)
PROG
(Magma) I:=[ 1, 2, 5, 112, 229, 570 ]; [n le 6 select I[n] else 114*Self(n-3)+Self(n-6): n in [1..40]]; // Vincenzo Librandi, Dec 13 2013
CROSSREFS
Sequence in context: A023263 A070855 A228850 * A221476 A015172 A132526
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Nov 14 2013
STATUS
approved