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A235213
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Nearest prime to (2^(e^-gamma))^n, where gamma is the Euler-Mascheroni constant.
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0
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2, 3, 5, 7, 11, 17, 23, 31, 47, 73, 107, 157, 233, 347, 509, 743, 1103, 1627, 2399, 3541, 5227, 7717, 11383, 16811, 24799, 36599, 54011, 79699, 117619, 173573, 256163, 378041, 557891, 823309, 1215017, 1793081, 2646167, 3905059, 5762969, 8504759, 12550991, 18522269
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OFFSET
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2,1
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COMMENTS
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The nearest integer to (2^(e^-gamma))^n is very close to A018133.
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LINKS
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FORMULA
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MATHEMATICA
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f[n_] := Block[{a = (2^Exp[-EulerGamma])^n}, Nearest[{NextPrime[a], NextPrime[a, -1]}, a][[1]]]; Array[f, 42, 2]
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PROG
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(PARI) a(n)=my(t=2^(exp(Euler)*n), mn=precprime(t), mx=nextprime(t)); if(mx-t<t-mn, mx, mn) \\ Charles R Greathouse IV, Jan 04 2014
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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