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A041445 Denominators of continued fraction convergents to sqrt(238). 2
1, 2, 5, 7, 103, 110, 323, 756, 23003, 46762, 116527, 163289, 2402573, 2565862, 7534297, 17634456, 536567977, 1090770410, 2718108797, 3808879207, 56042417695, 59851296902, 175745011499, 411341319900, 12515984608499, 25443310536898, 63402605682295 (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 (0,0,0,0,0,0,0,23326,0,0,0,0,0,0,0,-1).

FORMULA

G.f.: -(x^14 -2*x^13 +5*x^12 -7*x^11 +103*x^10 -110*x^9 +323*x^8 -756*x^7 -323*x^6 -110*x^5 -103*x^4 -7*x^3 -5*x^2 -2*x -1) / (x^16 -23326*x^8 +1). - Colin Barker, Nov 17 2013

a(n) = 23326*a(n-8) - a(n-16) for n>15. - Vincenzo Librandi, Dec 18 2013

MATHEMATICA

Denominator[Convergents[Sqrt[238], 30]] (* Vincenzo Librandi, Dec 18 2013 *)

PROG

(MAGMA) I:=[1, 2, 5, 7, 103, 110, 323, 756, 23003, 46762, 116527, 163289, 2402573, 2565862, 7534297, 17634456]; [n le 16 select I[n] else 23326*Self(n-8)-Self(n-16): n in [1..30]]; // Vincenzo Librandi, Dec 18 2013

CROSSREFS

Cf. A041444, A040222.

Sequence in context: A042257 A343833 A103056 * A265815 A041961 A242169

Adjacent sequences:  A041442 A041443 A041444 * A041446 A041447 A041448

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Nov 17 2013

STATUS

approved

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Last modified August 1 03:05 EDT 2021. Contains 346379 sequences. (Running on oeis4.)