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%I #23 Jun 13 2015 14:41:04
%S 19,37,97,157,199,229,271,307,337,379,577,601,661,727,811,829,877,937,
%T 997,1009,1069,1171,1237,1279,1297,1429,1459,1531,1609,1657,2029,2089,
%U 2137,2179,2221,2281,2467,2539,2551,2557,2617,2719,2791,2851,3037,3061,3109
%N Primes p such that p + phi(p) + mu(phi(p)) is also prime.
%C For these terms, mu(phi(p)) must be zero.
%C For prime p, phi(p) = p-1, so terms are primes p such that 2p-1 is also prime (A005382) and p-1 is not squarefree. - _Jens Kruse Andersen_, Jul 19 2014
%H Jens Kruse Andersen, <a href="/A244111/b244111.txt">Table of n, a(n) for n = 1..10000</a>
%e a(1)=19 as 19+18+0 is prime.
%e a(2)=37 as 37+36+0 is prime.
%e a(3)=97 as 97+96+0 is prime.
%p with(numtheory): A244111:=n->`if`(isprime(n+phi(n)+mobius(phi(n))) and isprime(n),n,NULL); seq(A244111(n), n=1..5000); # _Wesley Ivan Hurt_, Jul 19 2014
%t apQ[n_]:=Module[{p=EulerPhi[n]},PrimeQ[n+p+MoebiusMu[p]]]; Select[Prime[ Range[500]],apQ] (* _Harvey P. Dale_, Jun 13 2015 *)
%o (PARI) isok(n) = isprime(n) && isprime(n + eulerphi(n) + moebius(eulerphi(n))); \\ _Michel Marcus_, Jun 21 2014
%Y Cf. A000010, A005382, A008683.
%K nonn
%O 1,1
%A _Torlach Rush_, Jun 20 2014
%E More terms from _Michel Marcus_, Jun 21 2014
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