This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A058501 #12 Jul 07 2022 08:11:54
%S A058501 2,3,5,17,19,31,37,43,61,67,71,73,79,101,103,109,127,131,139,151,157,
%T A058501 163,181,191,197,199,211,223,229,239,241,251,257,271,277,281,283,307,
%U A058501 311,313,331,337,349,367,373,379,397,401,409,419,421,431,433,439,443
%N A058501 Primes p such that largest odd factor of p-1 is not a prime (i.e., is composite or 1).
%H A058501 Amiram Eldar, <a href="/A058501/b058501.txt">Table of n, a(n) for n = 1..10000</a>
%F A058501 Nonprimes in A057023.
%e A058501 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 A058501 lofQ[n_]:=Module[{c=Select[Divisors[n-1],OddQ][[-1]]},!PrimeQ[c]]; Select[ Prime[ Range[100]],lofQ] (* _Harvey P. Dale_, Jul 24 2021 *)
%Y A058501 Cf. A057023, A006093.
%K A058501 nonn
%O A058501 1,1
%A A058501 _Labos Elemer_, Dec 20 2000