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A259490
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Numbers k such that the denominator of the n-th convergent of the continued fraction expansion of Pi is prime.
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0
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OFFSET
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1,1
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COMMENTS
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a(11) > 25000.
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LINKS
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MATHEMATICA
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$MaxExtraPrecision = 25000; lst = {}; cf = ContinuedFraction[Pi, 10000]; Do[ If[ PrimeQ[ Denominator[ FromContinuedFraction[ Take[ cf, n]] ]], AppendTo[lst, n]], {n, Length[cf]}]; lst
Position[Convergents[Pi, 7000], _?(PrimeQ[Denominator[#]]&)]//Flatten (* Harvey P. Dale, Aug 12 2021 *)
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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