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Primes of the form floor( exp(n) ).
5

%I #12 Oct 17 2019 22:55:07

%S 2,7,65659969,5184705528587072464087,

%T 14302079958348104463583671072905261080748384225250684971,

%U 17199742630376622641833783925547830057256484050709158699244513

%N Primes of the form floor( exp(n) ).

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

%e a(3) = floor(e^18) = 65659969, which is prime.

%t Select[Table[Floor[Exp[n]], {n, 150}], PrimeQ] (* _Jayanta Basu_, Jun 01 2013 *)

%Y Cf. A050808 (values of n), A000149, A040016, A037028, A000227, A004791.

%K nonn,hard

%O 1,1

%A _Patrick De Geest_, Oct 15 1999

%E Corrected by _Naohiro Nomoto_, Feb 22 2001