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A042454 Numerators of continued fraction convergents to sqrt(755). 2
27, 55, 577, 1209, 65863, 132935, 1395213, 2923361, 159256707, 321436775, 3373624457, 7068685689, 385082651663, 777233989015, 8157422541813, 17092079072641, 931129692464427, 1879351464001495 (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, 2418, 0, 0, 0, -1).

FORMULA

G.f.: (27 +55*x +577*x^2 +1209*x^3 +577*x^4 -55*x^5 +27* x^6 -x^7)/(1 -2418*x^4 +x^8). - Vincenzo Librandi, Nov 25 2013

a(n) = 2418*a(n-4) - a(n-8). - Vincenzo Librandi, Nov 25 2013

MATHEMATICA

Numerator[Convergents[Sqrt[755], 40]] (* Harvey P. Dale, Feb 25 2012 *)

CoefficientList[Series[(27 + 55 x + 577 x^2 + 1209 x^3 + 577 x^4 - 55 x^5 + 27 x^6 - x^7)/(1 - 2418 x^4 + x^8), {x, 0, 30}], x] (* Vincenzo Librandi, Nov 25 2013 *)

PROG

(MAGMA) I:=[27, 55, 577, 1209, 65863, 132935, 1395213, 2923361]; [n le 8 select I[n] else 2418*Self(n-4)-Self(n-8): n in [1..30]]; // Vincenzo Librandi, Nov 25 2013

CROSSREFS

Cf. A042455.

Sequence in context: A042446 A042450 A042452 * A042456 A132768 A053180

Adjacent sequences:  A042451 A042452 A042453 * A042455 A042456 A042457

KEYWORD

nonn,cofr,frac,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

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Last modified October 14 14:45 EDT 2019. Contains 328019 sequences. (Running on oeis4.)