A042583 Denominators of continued fraction convergents to sqrt(820).

1, 1, 2, 3, 8, 11, 118, 129, 376, 505, 881, 1386, 78497, 79883, 158380, 238263, 634906, 873169, 9366596, 10239765, 29846126, 40085891, 69932017, 110017908, 6230934865, 6340952773, 12571887638, 18912840411, 50397568460, 69310408871, 743501657170

Offset

0,3

Links

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

Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,0,0,0,0,0,0,79378,0,0,0,0,0,0,0,0,0,0,0,-1).

Formula

G.f.: -(x^2 -x -1)*(x^20 +3*x^18 +11*x^16 +129*x^14 +505*x^12 +1386*x^10 +505*x^8 +129*x^6 +11*x^4 +3*x^2 +1) / ((x^8 -43*x^4 +1)*(x^16 +43*x^12 +1848*x^8 +43*x^4 +1)). - Colin Barker, Dec 18 2013

Mathematica

Denominator[Convergents[Sqrt[820], 30]] (* Vincenzo Librandi, Jan 25 2014 *)

Crossrefs

Cf. A042582, A040791.

Sequence in context: A041587 A139447 A042783 * A128839 A368357 A192113

Adjacent sequences: A042580 A042581 A042582 * A042584 A042585 A042586

Keyword

nonn,frac,easy

Author

N. J. A. Sloane.

Extensions

More terms from Colin Barker, Dec 18 2013

Status

approved