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Primes p such that the nearest integer to p * e is prime.
2

%I #9 Jun 15 2013 01:51:28

%S 2,7,29,37,71,113,163,179,199,227,283,439,463,503,541,547,647,733,761,

%T 823,839,887,953,1031,1049,1051,1093,1327,1399,1549,1627,1741,1847,

%U 1861,1901,1951,2017,2053,2081,2179,2221,2287,2309,2399,2477,2591,2689,2711

%N Primes p such that the nearest integer to p * e is prime.

%H Vincenzo Librandi, <a href="/A116968/b116968.txt">Table of n, a(n) for n = 1..1000</a>

%t lst={};Do[p=Prime[n];If[PrimeQ[Round[p*E]],AppendTo[lst,p]],{n,10^3}];lst

%K nonn,easy

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Aug 25 2008

%E Edited by _Charles R Greathouse IV_, Nov 11 2009