A050809 Primes of the form floor( exp(k) ).

2, 7, 65659969, 5184705528587072464087, 14302079958348104463583671072905261080748384225250684971, 17199742630376622641833783925547830057256484050709158699244513

Offset: 1

Author

Patrick De Geest, Oct 15 1999

Keywords

• nonn
• hard

Examples

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

Links

• Amiram Eldar, Table of n, a(n) for n = 1..9
• Eric Weisstein's World of Mathematics, e-Prime.

Crossrefs

Cf. A050808 (values of k), A000149, A040016, A037028, A000227, A004791.

Programs

Mathematica

Select[Table[Floor[Exp[n]], {n, 150}], PrimeQ] (* Jayanta Basu, Jun 01 2013 *)

Extensions

Corrected by Naohiro Nomoto, Feb 22 2001