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 A153215 #16 Oct 01 2019 04:00:20
%S A153215 727,1423,1861,3719,6173,9749,11321,13183,19073,20873,23227,23473,
%T A153215 23827,26981,27883,34351,35323,41263,42677,44449,45127,45523,47527,
%U A153215 48751,49727,52391,53623,53849,68749,71993,72559,78823,83609,89227,92779
%N A153215 Primes p such that none of p-2, p-1, p+1, and p+2 is squarefree.
%H A153215 Amiram Eldar, <a href="/A153215/b153215.txt">Table of n, a(n) for n = 1..10000</a>
%t A153215 << NumberTheory`NumberTheoryFunctions` lst={}; Do[p=Prime[n];If[ !SquareFreeQ[p-1]&&!SquareFreeQ[p+1]&&!SquareFreeQ[p-2]&&!SquareFreeQ[p+2],AppendTo[lst,p]],{n,4*7!}]; lst
%Y A153215 Cf. A049282, A049097, A039787, A075432, A153207, A153208, A153209, A153210, A153213, A153214.
%K A153215 nonn
%O A153215 1,1
%A A153215 _Vladimir Joseph Stephan Orlovsky_, Dec 20 2008