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A235213 Nearest prime to (2^(e^-gamma))^n, where gamma is the Euler-Mascheroni constant. 0
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

The nearest integer to (2^(e^-gamma))^n is very close to A018133.

LINKS

Table of n, a(n) for n=2..43.

Eric W. Weisstein's World of Mathematics, Wagstaff's Conjecture

Eric W. Weisstein's World of Mathematics, Eberhart's Conjecture

FORMULA

Nearest prime to (2^(e^-A001620))^n = (2^A080130)^n.

MATHEMATICA

f[n_] := Block[{a = (2^Exp[-EulerGamma])^n}, Nearest[{NextPrime[a], NextPrime[a, -1]}, a][[1]]]; Array[f, 42, 2]

PROG

(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

CROSSREFS

Cf. A000043, A001620, A080130.

Sequence in context: A293074 A005105 A086566 * A188552 A104892 A065436

Adjacent sequences:  A235210 A235211 A235212 * A235214 A235215 A235216

KEYWORD

nonn,easy

AUTHOR

Robert G. Wilson v, Jan 04 2014

STATUS

approved

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Last modified April 18 22:08 EDT 2019. Contains 322237 sequences. (Running on oeis4.)