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Numbers k such that floor(e^k) + 1 is prime.
6

%I #23 Feb 13 2024 14:34:25

%S 0,1,5,7,10,105,22959,34888

%N Numbers k such that floor(e^k) + 1 is prime.

%C 0 followed by all k such that ceiling(e^k) is prime. - _Jeppe Stig Nielsen_, Feb 12 2024

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

%t Select[Range[40000], PrimeQ[Floor[E^#] + 1] &] (* _G. C. Greubel_, Jan 06 2017 *)

%o (PARI) isok(k) = isprime(floor(exp(k))+1) \\ _Michel Marcus_, Jun 08 2013

%Y Cf. A001671, A050808.

%K nonn,more

%O 1,3

%A _Felice Russo_, Jan 25 2001

%E Corrected by Francisco Salinas (franciscodesalinas(AT)hotmail.com), Dec 25 2001

%E a(7)-a(8) from _Donovan Johnson_