A042212 Numerators of continued fraction convergents to sqrt(632).

25, 176, 1081, 7743, 388231, 2725360, 16740391, 119908097, 6012145241, 42204924784, 259241693945, 1856896782399, 93104080813895, 653585462479664, 4014616855691879, 28755903452322817, 1441809789471832729

Offset

0,1

Links

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

Index entries for linear recurrences with constant coefficients, signature (0,0,0,15486,0,0,0,-1).

Formula

G.f.: (25 + 176*x + 1081*x^2 + 7743*x^3 + 1081*x^4 - 176*x^5 + 25*x^6 - x^7)/(1 - 15486*x^4 + x^8). - Vincenzo Librandi, Nov 19 2013

a(n) = 15486*a(n-4) - a(n-8). - Vincenzo Librandi, Nov 19 2013

Mathematica

Numerator[Convergents[Sqrt[632], 20]] (* Harvey P. Dale, Aug 06 2013 *)
CoefficientList[Series[(25 + 176 x + 1081 x^2 + 7743 x^3 + 1081 x^4 - 176 x^5 + 25 x^6 - x^7)/(1 - 15486 x^4 + x^8), {x, 0, 30}], x] (* Vincenzo Librandi, Nov 19 2013 *)

Prog

(Magma) I:=[25, 176, 1081, 7743, 388231, 2725360, 16740391, 119908097]; [n le 8 select I[n] else 15486*Self(n-4)-Self(n-8): n in [1..30]]; // Vincenzo Librandi, Nov 19 2013

Crossrefs

Cf. A042213.

Sequence in context: A201089 A020277 A200671 * A258319 A302562 A264259

Adjacent sequences: A042209 A042210 A042211 * A042213 A042214 A042215

Keyword

nonn,cofr,frac,easy

Author

N. J. A. Sloane.

Status

approved