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%I #9 Sep 08 2022 08:46:10
%S 2,5,7,13,17,19,23,29,31,43,47,59,61,67,71,73,89,97,101,103,109,113,
%T 127,131,137,139,149,151,157,163,167,179,181,191,193,197,199,211,223,
%U 229,233,241,251,257,263,269,277,281,283,293,307,311,313,331,337,349,353
%N Primes which do not divide any repunit number R(p) = (10^p - 1)/9 with p prime.
%C If a prime p has period n, then p divides 10^m - 1 for all m divisible by n. Therefore the sequence together with 3 is the complement in the primes of A072859.
%o (Magma) [2] cat [p: p in PrimesInInterval(5, 353) | not IsPrime(Modorder(10, p))];
%Y Cf. A072859.
%K nonn,base
%O 1,1
%A _Arkadiusz Wesolowski_, Oct 25 2014