A041715 Denominators of continued fraction convergents to sqrt(377).

1, 2, 5, 12, 461, 934, 2329, 5592, 214825, 435242, 1085309, 2605860, 100107989, 202821838, 505751665, 1214325168, 46650108049, 94514541266, 235679190581, 565872922428, 21738850242845, 44043573408118, 109825997059081, 263695567526280, 10130257563057721

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (0,0,0,466,0,0,0,-1).

Formula

G.f.: -(x^2-2*x-1)*(x^4+6*x^2+1) / (x^8-466*x^4+1). - Colin Barker, Nov 22 2013

a(n) = 466*a(n-4) - a(n-8) for n>7. - Vincenzo Librandi, Dec 23 2013

Mathematica

Denominator[Convergents[Sqrt[377], 30]] (* Vincenzo Librandi, Dec 23 2013 *)
LinearRecurrence[{0, 0, 0, 466, 0, 0, 0, -1}, {1, 2, 5, 12, 461, 934, 2329, 5592}, 40] (* Harvey P. Dale, Jul 24 2019 *)

Prog

(Magma) I:=[1, 2, 5, 12, 461, 934, 2329, 5592]; [n le 8 select I[n] else 466*Self(n-4)-Self(n-8): n in [1..40]]; // Vincenzo Librandi, Dec 23 2013

Crossrefs

Cf. A041714, A040357.

Sequence in context: A041095 A041333 A197950 * A042241 A042911 A137918

Adjacent sequences: A041712 A041713 A041714 * A041716 A041717 A041718

Keyword

nonn,frac,easy

Author

N. J. A. Sloane.

Extensions

More terms from Colin Barker, Nov 22 2013

Status

approved