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A050808 Numbers n such that floor(exp(n)) is prime. 5

%I

%S 1,2,18,50,127,141,267,310,2290,4487,5391,14025

%N Numbers n such that floor(exp(n)) is prime.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/e-Prime.html">e-Prime</a>

%t Do[ If[ PrimeQ[ Floor[ \[ExponentialE]^n] ], Print[n] ], {n, 0, 4750} ]

%t Select[Range[15000],PrimeQ[Floor[Exp[#]]]&] (* _Harvey P. Dale_, Oct 16 2012 *)

%o (PARI) is(n)=ispseudoprime(exp(n)\1) \\ _Charles R Greathouse IV_, Jan 03 2014

%Y Cf. A050809 (the actual primes), A000149, A040016, A037028, A000227, A004791, A059791, A059792.

%K nonn,hard

%O 1,2

%A _Patrick De Geest_, Oct 15 1999

%E Corrected by _Naohiro Nomoto_, Feb 22 2001

%E More terms from _Vladeta Jovovic_, Feb 24 2001

%E More terms from _Robert G. Wilson v_, May 09 2001

%E a(11) = 5391 from _Eric W. Weisstein_, May 01 2006

%E a(12) from _Donovan Johnson_, Feb 04 2008

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Last modified May 23 20:23 EDT 2019. Contains 323528 sequences. (Running on oeis4.)