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A319050
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Primes p such that neither p + 1 nor p + 2 is squarefree.
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2
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7, 23, 43, 47, 79, 97, 151, 167, 223, 241, 331, 349, 359, 367, 439, 523, 547, 619, 691, 727, 773, 823, 839, 907, 1051, 1087, 1123, 1223, 1231, 1249, 1303, 1367, 1423, 1447, 1483, 1523, 1571, 1627, 1663, 1699, 1723, 1811, 1823, 1847, 1861, 1879, 1951, 1987, 2131, 2203, 2207
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OFFSET
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1,1
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LINKS
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EXAMPLE
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8 = 2^3 and 9 = 3^2. So 7 is a term.
24 = 2^3*3 and 25 = 5^2. So 23 is a term.
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MATHEMATICA
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Select[Prime[Range[400]], NoneTrue[#+{1, 2}, SquareFreeQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Apr 05 2019 *)
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PROG
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(PARI) isok(p) = isprime(p) && !issquarefree(p+1) && !issquarefree(p+2); \\ Michel Marcus, Sep 09 2018
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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