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A041253 Denominators of continued fraction convergents to sqrt(138). 2
1, 1, 3, 4, 91, 95, 281, 376, 8553, 8929, 26411, 35340, 803891, 839231, 2482353, 3321584, 75557201, 78878785, 233314771, 312193556, 7101573003, 7413766559, 21929106121, 29342872680, 667472305081, 696815177761, 2061102660603, 2757917838364, 62735295104611 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

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

Index entries for linear recurrences with constant coefficients, signature (0,0,0,94,0,0,0,-1).

FORMULA

G.f.: -(x^2-x-1)*(x^4+4*x^2+1) / (x^8-94*x^4+1). - Colin Barker, Nov 14 2013

a(n) = 94*a(n-4) - a(n-8). - Vincenzo Librandi, Dec 13 2013

MATHEMATICA

Denominator[Convergents[Sqrt[138], 30]]  (* Vincenzo Librandi, Dec 13 2013 *)

PROG

(MAGMA) I:=[1, 1, 3, 4, 91, 95, 281, 376]; [n le 8 select I[n] else 94*Self(n-4)-Self(n-8): n in [1..40]]; // Vincenzo Librandi, Dec 13 2013

CROSSREFS

Cf. A041252, A010197.

Sequence in context: A111799 A135237 A316197 * A297119 A156182 A126578

Adjacent sequences:  A041250 A041251 A041252 * A041254 A041255 A041256

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 November 18 04:44 EST 2019. Contains 329248 sequences. (Running on oeis4.)