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A042485 Denominators of continued fraction convergents to sqrt(770). 2
1, 1, 3, 4, 219, 223, 665, 888, 48617, 49505, 147627, 197132, 10792755, 10989887, 32772529, 43762416, 2395942993, 2439705409, 7275353811, 9715059220, 531888551691, 541603610911, 1615095773513, 2156699384424, 118076862532409, 120233561916833, 358543986366075 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
FORMULA
G.f.: -(x^2 -x -1)*(x^4 +4*x^2 +1) / (x^8 -222*x^4 +1). - Colin Barker, Dec 15 2013
a(n) = 222*a(n-4) - a(n-8). - Vincenzo Librandi, Dec 15 2013
MATHEMATICA
Denominator[Convergents[Sqrt[770], 30]] (* Vincenzo Librandi, Dec 15 2013 *)
PROG
(Magma) I:=[1, 1, 3, 4, 219, 223, 665, 888]; [n le 8 select I[n] else 222*Self(n-4)-Self(n-8): n in [1..40]]; // Vincenzo Librandi, Dec 15 2013
CROSSREFS
Sequence in context: A042275 A012861 A349885 * A111315 A042711 A195566
KEYWORD
nonn,frac,easy
AUTHOR
EXTENSIONS
More terms from Colin Barker, Dec 15 2013
STATUS
approved

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Last modified June 19 12:43 EDT 2024. Contains 373503 sequences. (Running on oeis4.)