A042425 Denominators of continued fraction convergents to sqrt(740).

1, 4, 5, 64, 69, 340, 18429, 74056, 92485, 1183876, 1276361, 6289320, 340899641, 1369887884, 1710787525, 21899338184, 23610125709, 116339841020, 6305961540789, 25340186004176, 31646147544965, 405093956543756, 436740104088721, 2152054372898640

Offset

0,2

Links

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

Index entries for linear recurrences with constant coefficients, signature (0,0,0,0,0,18498,0,0,0,0,0,-1).

Formula

G.f.: -(x^10-4*x^9+5*x^8-64*x^7+69*x^6-340*x^5-69*x^4-64*x^3-5*x^2-4*x-1) / ((x^6-136*x^3-1)*(x^6+136*x^3-1)). - Colin Barker, Dec 12 2013

Mathematica

Denominator[Convergents[Sqrt[740], 30]] (* Vincenzo Librandi, Jan 22 2014 *)
LinearRecurrence[{0, 0, 0, 0, 0, 18498, 0, 0, 0, 0, 0, -1}, {1, 4, 5, 64, 69, 340, 18429, 74056, 92485, 1183876, 1276361, 6289320}, 30] (* Harvey P. Dale, Oct 22 2023 *)

Crossrefs

Cf. A042424, A040712.

Sequence in context: A341575 A013331 A226145 * A109348 A192084 A078985

Adjacent sequences: A042422 A042423 A042424 * A042426 A042427 A042428

Keyword

nonn,frac,easy

Author

N. J. A. Sloane.

Extensions

More terms from Colin Barker, Dec 12 2013

Status

approved