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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.

A318959 Primes p (> 2) such that p - 2 and p - 1 are nonsquarefree.

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%I A318959 #38 Sep 08 2022 08:46:23
%S A318959 29,101,127,137,149,173,277,281,317,353,389,461,509,541,569,577,641,
%T A318959 677,727,821,857,877,929,977,1109,1129,1181,1217,1277,1289,1361,1423,
%U A318959 1433,1451,1613,1667,1721,1777,1861,1877,1901,1913,1973,2081,2153,2297,2333,2351
%N A318959 Primes p (> 2) such that p - 2 and p - 1 are nonsquarefree.
%H A318959 Seiichi Manyama, <a href="/A318959/b318959.txt">Table of n, a(n) for n = 1..10000</a>
%e A318959 21 (= 23 - 2) is squarefree. So 23 is not a term.
%e A318959 27 = 3^3 and 28 = 2^2*7. So 29 is a term.
%t A318959 Select[Prime[Range[500]], !SquareFreeQ[# - 2] && !SquareFreeQ[# - 1] &] (* _Vincenzo Librandi_, Sep 06 2018 *)
%o A318959 (PARI) forprime(p=2, 1e4, if(!issquarefree(p-1)&&!issquarefree(p-2), print1(p, ", "))); \\ _Altug Alkan_, Sep 06 2018
%o A318959 (Magma) [p: p in PrimesInInterval(3, 2500)| not IsSquarefree(p-2) and not IsSquarefree(p-1)]; // _Vincenzo Librandi_, Sep 06 2018
%Y A318959 Cf. A000040, A039787, A049231, A240473, A257545, A319049.
%K A318959 nonn
%O A318959 1,1
%A A318959 _Seiichi Manyama_, Sep 06 2018