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 A087749 #14 Feb 16 2021 01:00:27
%S A087749 3,7,17,19,29,31,37,41,43,47,53,59,67,71,73,79,89,97,101,103,107,109,
%T A087749 113,127,131,137,139,149,151,157,163,167,173,179,181,191,193,197,199,
%U A087749 211,223,227,229,233,239,241,251,257,263,269,271,277,281
%N A087749 Primes p such that 6^p - 5^p is composite.
%t A087749 Select[Prime[Range[60]],!PrimeQ[6^#-5^#]&] (* _Harvey P. Dale_, Apr 26 2011 *)
%o A087749 (PARI) apmb(a,b,n) = { forprime(x=2,n, y=a^x-b^x; if(!ispseudoprime(y), print1(x","); ) ) }
%Y A087749 Cf. A005062.
%K A087749 nonn
%O A087749 1,1
%A A087749 _Cino Hilliard_, Oct 26 2003
%E A087749 Corrected by _Andrew S. Plewe_, Apr 24 2007 (all the terms were wrong)
%E A087749 Checked by _Ray Chandler_, Apr 25 2007