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A042212 Numerators of continued fraction convergents to sqrt(632). 2
25, 176, 1081, 7743, 388231, 2725360, 16740391, 119908097, 6012145241, 42204924784, 259241693945, 1856896782399, 93104080813895, 653585462479664, 4014616855691879, 28755903452322817, 1441809789471832729 (list; graph; refs; listen; history; text; internal format)
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

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Last modified October 3 22:17 EDT 2022. Contains 357237 sequences. (Running on oeis4.)