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%I #20 Sep 08 2022 08:45:05
%S 1,2,3,7,15,19,31,33,35,37,51,65,69,77,79,85,91,95,97,133,139,141,143,
%T 145,157,159,161,177,187,199,209,211,213,215,217,229,235,247,255,267,
%U 271,299,303,307,319,331,335,337,339,341,345,365,367,371,379,391,393
%N Integers n such that n + phi(n) is a prime.
%C The subsequence of prime terms is given by A005382. - _Michel Marcus_, Aug 22 2015
%H Amiram Eldar, <a href="/A068080/b068080.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Range[400], PrimeQ[# + EulerPhi[#]] &] (* _Carl Najafi_, Aug 22 2011 *)
%o (PARI) isok(n) = isprime(n+eulerphi(n)); \\ _Michel Marcus_, Aug 22 2015
%o (Magma) [n: n in [1..400] |IsPrime(n+EulerPhi(n))]; // _Vincenzo Librandi_, Dec 19 2015
%Y Cf. A050530.
%K easy,nonn
%O 1,2
%A _Amarnath Murthy_, Feb 17 2002
%E Edited and extended by _Robert G. Wilson v_, Feb 18 2002
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