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Primes p such that p+5==0 (mod phi(p+5)).
1

%I #9 Jan 14 2022 15:14:32

%S 3,7,11,13,19,31,43,59,67,103,139,157,211,251,283,379,571,643,859,967,

%T 1019,1291,1453,1531,1723,3067,4091,4603,5179,5827,6907,17491,18427,

%U 20731,24571,41467,55291,82939,93307,98299,104971,110587,118093,147451

%N Primes p such that p+5==0 (mod phi(p+5)).

%H Harvey P. Dale, <a href="/A067542/b067542.txt">Table of n, a(n) for n = 1..75</a>

%t Select[Prime[Range[14000]],Mod[#+5,EulerPhi[#+5]]==0&] (* _Harvey P. Dale_, Jan 14 2022 *)

%K easy,nonn

%O 1,1

%A _Benoit Cloitre_, Feb 22 2002