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A064118
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Numbers n such that the first n digits of e form a prime.
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12
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OFFSET
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1,2
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COMMENTS
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The primes are given in A007512. Sequences A065815, A119344, A136583, A210706,... are analogs for gamma, sqrt(3), sqrt(10), 3^(1/3),.... The MathWorld page about "Constant Primes" lists further examples. - M. F. Hasler, Aug 31 2013
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REFERENCES
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C. A. Pickover, The Mathematics of Oz, "2, 271, 2718281", Chapter 95, Camb.Univ.Press, UK 2002.
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LINKS
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Table of n, a(n) for n=1..8.
Eric Weisstein's World of Mathematics, Constant Primes
Eric Weisstein's World of Mathematics, e Digits
Eric Weisstein's World of Mathematics, e-Prime
Eric Weisstein's World of Mathematics, Integer Sequence Primes
Index entries related to "constant primes".
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EXAMPLE
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a(2)=3 because 271 is prime.
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MATHEMATICA
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Do[If[PrimeQ[FromDigits[RealDigits[N[E, n + 10], 10, n][[1]]]], Print[n]], {n, 1, 2300}]
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CROSSREFS
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Cf. A001113.
Cf. A047658.
Sequence in context: A219588 A219375 A326427 * A041705 A137130 A058379
Adjacent sequences: A064115 A064116 A064117 * A064119 A064120 A064121
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KEYWORD
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base,more,nonn
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AUTHOR
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Shyam Sunder Gupta, Sep 09 2001
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EXTENSIONS
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One more term from Robert G. Wilson v, Sep 28 2001
a(6) from Eric W. Weisstein, Jan 17 2005
a(7) from Eric W. Weisstein, Jul 03 2009
a(8) from Eric W. Weisstein, Oct 11 2010
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STATUS
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approved
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