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A042741 Denominators of continued fraction convergents to sqrt(901). 2
1, 60, 3601, 216120, 12970801, 778464180, 46720821601, 2804027760240, 168288386436001, 10100107213920300, 606174721221654001, 36380583380513160360, 2183441177552011275601, 131042851236501189696420, 7864754515367623393060801, 472016313773293904773344480 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

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

Tanya Khovanova, Recursive Sequences

Index entries for linear recurrences with constant coefficients, signature (60, 1).

FORMULA

a(n) = F(n, 60), the n-th Fibonacci polynomial evaluated at x=60. - T. D. Noe, Jan 19 2006

From Philippe Deléham, Nov 23 2008: (Start)

a(n) = 60*a(n-1) + a(n-2) for n>1; a(0)=1, a(1)=60.

G.f.: 1/(1 - 60*x - x^2). (End)

MATHEMATICA

a=0; lst={}; s=0; Do[a=s-(a-1); AppendTo[lst, a]; s+=a*60, {n, 3*4!}]; lst (* Vladimir Joseph Stephan Orlovsky, Nov 03 2009 *)

Denominator[Convergents[Sqrt[901], 30]] (* or *) LinearRecurrence[{60, 1}, {1, 60}, 30] (* Harvey P. Dale, Sep 09 2012 *)

PROG

(MAGMA) I:=[1, 60]; [n le 2 select I[n] else 60*Self(n-1)+Self(n-2): n in [1..30]]; // Vincenzo Librandi, Jan 28 2014

CROSSREFS

Cf. A042740, A040870.

Sequence in context: A267930 A267977 A159991 * A166772 A293091 A074076

Adjacent sequences:  A042738 A042739 A042740 * A042742 A042743 A042744

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane

EXTENSIONS

Additional term  from Colin Barker, Dec 22 2013

STATUS

approved

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Last modified November 24 07:58 EST 2017. Contains 295173 sequences.