A042236 Numerators of continued fraction convergents to sqrt(644).

25, 51, 76, 127, 203, 1345, 1548, 2893, 4441, 11775, 593191, 1198157, 1791348, 2989505, 4780853, 31674623, 36455476, 68130099, 104585575, 277301249, 13969648025, 28216597299, 42186245324, 70402842623, 112589087947, 745937370305, 858526458252, 1604463828557

Offset

0,1

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, 23550, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1).

Formula

G.f.: -(x^19 -25*x^18 +51*x^17 -76*x^16 +127*x^15 -203*x^14 +1345*x^13 -1548*x^12 +2893*x^11 -4441*x^10 -11775*x^9 -4441*x^8 -2893*x^7 -1548*x^6 -1345*x^5 -203*x^4 -127*x^3 -76*x^2 -51*x -25) / (x^20 -23550*x^10 +1). - Colin Barker, Dec 05 2013

Mathematica

Numerator[Convergents[Sqrt[644], 30]] (* Vincenzo Librandi, Nov 19 2013 *)

Crossrefs

Cf. A042237, A040618.

Sequence in context: A360017 A034025 A253017 * A042238 A042234 A042232

Adjacent sequences: A042233 A042234 A042235 * A042237 A042238 A042239

Keyword

nonn,cofr,frac,easy

Author

N. J. A. Sloane.

Extensions

More terms from Colin Barker, Dec 05 2013

Status

approved