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A042811 Denominators of continued fraction convergents to sqrt(936). 2
1, 1, 2, 5, 32, 69, 101, 170, 10301, 10471, 20772, 52015, 332862, 717739, 1050601, 1768340, 107151001, 108919341, 216070342, 541060025, 3462430492, 7465921009, 10928351501, 18394272510, 1114584702101, 1132978974611, 2247563676712, 5628106328035 (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, 0, 0, 0, 0, 10402, 0, 0, 0, 0, 0, 0, 0, -1).

FORMULA

G.f.: -(x^14 -x^13 +2*x^12 -5*x^11 +32*x^10 -69*x^9 +101*x^8 -170*x^7 -101*x^6 -69*x^5 -32*x^4 -5*x^3 -2*x^2 -x -1) / ((x^4 -10*x^2 -1)*(x^4 +10*x^2 -1)*(x^8 +102*x^4 +1)). - Colin Barker, Dec 23 2013

a(n) = 10402*a(n-8) - a(n-16) for n>15. - Vincenzo Librandi, Jan 30 2014

MATHEMATICA

Denominator/@Convergents[Sqrt[936], 30]  (* Harvey P. Dale, Apr 18 2011 *)

PROG

(MAGMA) I:=[1, 1, 2, 5, 32, 69, 101, 170, 10301, 10471, 20772, 52015, 332862, 717739, 1050601, 1768340]; [n le 16 select I[n] else 10402*Self(n-8)-Self(n-16): n in [1..30]]; // Vincenzo Librandi, Jan 30 2014

CROSSREFS

Cf. A042810, A040905.

Sequence in context: A182327 A032504 A041397 * A261045 A145656 A221680

Adjacent sequences:  A042808 A042809 A042810 * A042812 A042813 A042814

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Dec 23 2013

STATUS

approved

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Last modified March 19 13:08 EDT 2019. Contains 321330 sequences. (Running on oeis4.)