A042787 Denominators of continued fraction convergents to sqrt(924).

1, 2, 3, 5, 73, 78, 151, 380, 22951, 46282, 69233, 115515, 1686443, 1801958, 3488401, 8778760, 530214001, 1069206762, 1599420763, 2668627525, 38960206113, 41628833638, 80589039751, 202806913140, 12249003828151, 24700814569442, 36949818397593

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, 23102, 0, 0, 0, 0, 0, 0, 0, -1).

Formula

G.f.: -(x^14 -2*x^13 +3*x^12 -5*x^11 +73*x^10 -78*x^9 +151*x^8 -380*x^7 -151*x^6 -78*x^5 -73*x^4 -5*x^3 -3*x^2 -2*x -1) / ((x^8 -152*x^4 +1)*(x^8 +152*x^4 +1)). - Colin Barker, Dec 23 2013

Maple

convert(sqrt(924), confrac, 30, cvgts): denom(cvgts); # Wesley Ivan Hurt, Dec 23 2013

Mathematica

Denominator[Convergents[Sqrt[924], 30]] (* Wesley Ivan Hurt, Dec 23 2013 *)
CoefficientList[Series[-(x^14 - 2 x^13 + 3 x^12 - 5 x^11 + 73 x^10 - 78 x^9 + 151 x^8 - 380 x^7 - 151 x^6 - 78 x^5 - 73 x^4 - 5 x^3 - 3 x^2 - 2 x - 1)/((x^8 - 152 x^4 + 1) (x^8 + 152 x^4 + 1)), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 23 2013 *)

Crossrefs

Cf. A042786, A040893.

Sequence in context: A270582 A270916 A029975 * A270355 A041131 A084960

Adjacent sequences: A042784 A042785 A042786 * A042788 A042789 A042790

Keyword

nonn,frac,easy

Author

N. J. A. Sloane.

Extensions

More terms from Colin Barker, Dec 23 2013

Status

approved