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A042228 Numerators of continued fraction convergents to sqrt(640). 2
25, 76, 177, 253, 1189, 1442, 17051, 18493, 91023, 109516, 310055, 1039681, 52294105, 157921996, 368138097, 526060093, 2472378469, 2998438562, 35455202651, 38453641213, 189269767503, 227723408716, 644716584935, 2161873163521, 108738374760985, 328376997446476 (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 (0,0,0,0,0,0,0,0,0,0,0,2079362,0,0,0,0,0,0,0,0,0,0,0,-1).

FORMULA

G.f.: -(x^23 -25*x^22 +76*x^21 -177*x^20 +253*x^19 -1189*x^18 +1442*x^17 -17051*x^16 +18493*x^15 -91023*x^14 +109516*x^13 -310055*x^12 -1039681*x^11 -310055*x^10 -109516*x^9 -91023*x^8 -18493*x^7 -17051*x^6 -1442*x^5 -1189*x^4 -253*x^3 -177*x^2 -76*x -25) / ((x^6 -38*x^3 +1)*(x^6 +38*x^3 +1)*(x^12 +1442*x^6 +1)). - Colin Barker, Dec 04 2013

MATHEMATICA

Numerator[Convergents[Sqrt[640], 30]] (* Harvey P. Dale, Jul 03 2013 *)

CROSSREFS

Cf. A042229, A040614.

Sequence in context: A008852 A042226 A042224 * A042230 A189642 A221309

Adjacent sequences:  A042225 A042226 A042227 * A042229 A042230 A042231

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Dec 04 2013

STATUS

approved

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Last modified December 9 22:27 EST 2019. Contains 329880 sequences. (Running on oeis4.)