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A109615
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Primes of the form floor((Pi/2)^n).
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1
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2, 3, 23, 37, 1373, 3389, 8363, 115459401415242179, 45851925215547567394556916118490828192232481476091362012033249370219, 1299908856087615767823951491725300134515972513464867209212961415385730635249
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OFFSET
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1,1
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COMMENTS
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The given terms of the sequence correspond to n=2, 3, 7, 8, 16, 18, 20 respectively. There are no other terms for n=21..100000. - Emeric Deutsch, Aug 27 2007
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LINKS
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EXAMPLE
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A014214(20) = floor((Pi/2)^20) = floor(8363.6825...) = 8363 and 8363 = A000040(1047), therefore 8363 is a term.
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MAPLE
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a:=proc(n) if isprime(floor(((1/2)*Pi)^n))=true then floor(((1/2)*Pi)^n) else end if end proc: seq(a(n), n=1..100); # Emeric Deutsch, Aug 27 2007
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MATHEMATICA
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lst={}; Do[If[PrimeQ[p=Floor[(Pi/2)^n]], AppendTo[lst, p]], {n, 600}
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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