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%I #19 Sep 10 2018 07:58:06
%S 47,97,241,349,547,773,1249,1447,1663,1847,1861,2347,2887,3049,3547,
%T 3607,3623,3697,4111,4373,4597,5237,5273,5749,6173,6857,7549,8467,
%U 8647,8719,9161,9349,9547,9749,11149,11321,11447,12049,12473,12689,12823,12941,13147,13291
%N Primes p such that none of p + 1, p + 2 and p + 3 are squarefree.
%H Seiichi Manyama, <a href="/A319051/b319051.txt">Table of n, a(n) for n = 1..10000</a>
%e 48 = 2^4*3, 49 = 7^2 and 50 = 2*5^2. So 47 is a term.
%e 98 = 2*7^2, 99 = 3^2*11 and 100 = 2^2*5^2. So 97 is a term.
%o (PARI) forprime(p=2, 1e5, if(!issquarefree(p+1) && !issquarefree(p+2) && !issquarefree(p+3), print1(p", ")))
%Y Cf. A000040, A049098, A257108, A319049, A319050.
%K nonn
%O 1,1
%A _Seiichi Manyama_, Sep 08 2018