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%I #12 Jul 07 2022 08:11:54
%S 2,3,5,17,19,31,37,43,61,67,71,73,79,101,103,109,127,131,139,151,157,
%T 163,181,191,197,199,211,223,229,239,241,251,257,271,277,281,283,307,
%U 311,313,331,337,349,367,373,379,397,401,409,419,421,431,433,439,443
%N Primes p such that largest odd factor of p-1 is not a prime (i.e., is composite or 1).
%H Amiram Eldar, <a href="/A058501/b058501.txt">Table of n, a(n) for n = 1..10000</a>
%F Nonprimes in A057023.
%e 127 is here because 127 - 1 = 126 = 2*63 and 63 is not a prime. 2 is here because 2 - 1 = 1 = 1*2^0 and 1 is not a prime.
%t lofQ[n_]:=Module[{c=Select[Divisors[n-1],OddQ][[-1]]},!PrimeQ[c]]; Select[ Prime[ Range[100]],lofQ] (* _Harvey P. Dale_, Jul 24 2021 *)
%Y Cf. A057023, A006093.
%K nonn
%O 1,1
%A _Labos Elemer_, Dec 20 2000
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