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A042238 Numerators of continued fraction convergents to sqrt(645). 2
25, 51, 76, 127, 1600, 16127, 195124, 211251, 406375, 1024001, 51606425, 104236851, 155843276, 260080127, 3276804800, 33028128127, 399614342324, 432642470451, 832256812775, 2097156096001, 105690061612825, 213477279321651, 319167340934476, 532644620256127 (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, 0, 0, 0, 0, 0, 0, 2048002, 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 -1600*x^14 +16127*x^13 -195124*x^12 +211251*x^11 -406375*x^10 -1024001*x^9 -406375*x^8 -211251*x^7 -195124*x^6 -16127*x^5 -1600*x^4 -127*x^3 -76*x^2 -51*x -25) / (x^20 -2048002*x^10 +1). - Colin Barker, Dec 05 2013

MATHEMATICA

Numerator[Convergents[Sqrt[645], 30]] (* Vincenzo Librandi, Nov 19 2013 *)

CROSSREFS

Cf. A042239, A040619.

Sequence in context: A034025 A253017 A042236 * A042234 A042232 A273868

Adjacent sequences:  A042235 A042236 A042237 * A042239 A042240 A042241

KEYWORD

nonn,cofr,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Dec 05 2013

STATUS

approved

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Last modified July 27 08:33 EDT 2021. Contains 346304 sequences. (Running on oeis4.)