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 A267506 #21 Feb 16 2021 02:10:24
%S A267506 2,3,7,43,103,239,479,619,3347,4327,10039,24379,25999,30703,48859,
%T A267506 123583,143879,147703,150587,170647,186019,288359,344639,421639,
%U A267506 593003,689279,690719,1029827,1381439,1779007,2651899,3089479,3558019,4242983
%N A267506 Primes p such that p-1 is squarefree and all prime divisors of p-1 other than 17 are also in the sequence.
%C A267506 Is this sequence infinite?
%t A267506 fa = FactorInteger; is[2, p_] = True; is[2, p_];
%t A267506 is[n_, p_] := PrimeQ[n] && MoebiusMu[n - 1] ≠ 0 && Union@Table[is[fa[n - 1][[i, 1]], p] || fa[n - 1][[ i, 1]] == p , {i, Length[fa[n - 1]]}] == {True}; Select[Prime[Range[10000]], is[#, 17] &]
%Y A267506 Cf. A267503, A267504, A267505, A267507, A005117, A227455, A227007, A227006.
%K A267506 nonn
%O A267506 1,1
%A A267506 _José María Grau Ribas_, Jan 16 2016