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A041237 Denominators of continued fraction convergents to sqrt(130). 2
1, 2, 5, 112, 229, 570, 12769, 26108, 64985, 1455778, 2976541, 7408860, 165971461, 339351782, 844675025, 18922202332, 38689079689, 96300361710, 2157297037309, 4410894436328, 10979085909965, 245950784455558, 502880654821081, 1251712094097720 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (0,0,114,0,0,1).

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

Cf. A041236, A040118.

Sequence in context: A023263 A070855 A228850 * A221476 A015172 A132526

Adjacent sequences:  A041234 A041235 A041236 * A041238 A041239 A041240

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Nov 14 2013

STATUS

approved

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Last modified August 9 20:09 EDT 2020. Contains 336326 sequences. (Running on oeis4.)