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A040446
Continued fraction for sqrt(468).
2
21, 1, 1, 1, 2, 1, 1, 1, 42, 1, 1, 1, 2, 1, 1, 1, 42, 1, 1, 1, 2, 1, 1, 1, 42, 1, 1, 1, 2, 1, 1, 1, 42, 1, 1, 1, 2, 1, 1, 1, 42, 1, 1, 1, 2, 1, 1, 1, 42, 1, 1, 1, 2, 1, 1, 1, 42, 1, 1, 1, 2, 1, 1, 1, 42, 1, 1, 1, 2, 1, 1, 1, 42, 1, 1, 1, 2, 1, 1, 1, 42, 1, 1, 1, 2, 1, 1, 1
OFFSET
0,1
FORMULA
From Amiram Eldar, Dec 26 2023: (Start)
Multiplicative with a(2) = 1, a(4) = 2, a(2^e) = 42 for e >= 3, and a(p^e) = 1 for an odd prime p.
Dirichlet g.f.: zeta(s) * (1 + 1/2^(2*s) + 5/2^(3*s-3)). (End)
MAPLE
with(numtheory): Digits := 300: convert(evalf(sqrt(468)), confrac);
MATHEMATICA
ContinuedFraction[Sqrt[468], 100] (* or *) PadRight[{21}, 100, {42, 1, 1, 1, 2, 1, 1, 1}] (* Harvey P. Dale, Feb 28 2015 *)
CROSSREFS
Sequence in context: A110454 A265156 A040445 * A040447 A040444 A040443
KEYWORD
nonn,cofr,easy,less,mult
STATUS
approved