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A042660 Numerators of continued fraction convergents to sqrt(860). 2
29, 88, 1261, 3871, 225779, 681208, 9762691, 29969281, 1747980989, 5273912248, 75582752461, 232022169631, 13532868591059, 40830627942808, 585161659790371, 1796315607313921, 104771466883997789, 316110716259307288 (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 (0,0,0,7742,0,0,0,-1).

FORMULA

G.f.: (29 +88*x +1261*x^2 +3871*x^3 +1261*x^4 -88*x^5 +29*x^6 -x^7)/(1 -7742*x^4 +x^8). - Vincenzo Librandi, Nov 30 2013

a(n) = 7742*a(n-4) - a(n-8). - Vincenzo Librandi, Nov 30 2013

MATHEMATICA

Numerator[Convergents[Sqrt[860], 30]] (* Harvey P. Dale, Mar 04 2013 *)

CoefficientList[Series[(29 + 88 x + 1261 x^2 + 3871 x^3 + 1261 x^4 - 88 x^5 + 29 x^6 - x^7)/(1 - 7742 x^4 + x^8), {x, 0, 30}], x]  (* Vincenzo Librandi, Nov 30 2013 *)

PROG

(MAGMA) I:=[29, 88, 1261, 3871, 225779, 681208, 9762691, 29969281]; [n le 8 select I[n] else 7742*Self(n-4)-Self(n-8): n in [1..30]]; // Vincenzo Librandi, Nov 30 2013

CROSSREFS

Cf. A042661.

Sequence in context: A042652 A042656 A042658 * A047650 A141883 A142791

Adjacent sequences:  A042657 A042658 A042659 * A042661 A042662 A042663

KEYWORD

nonn,cofr,frac,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified May 21 00:56 EDT 2019. Contains 323429 sequences. (Running on oeis4.)