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A259189
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Semiprimes of the form n^3 + 2.
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1
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10, 218, 514, 731, 1333, 2199, 2746, 3377, 4915, 5834, 6861, 8002, 9263, 12169, 15627, 29793, 35939, 42877, 54874, 59321, 68923, 117651, 125002, 132653, 148879, 185195, 205381, 314434, 405226, 421877, 474554, 531443, 592706, 658505, 704971
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OFFSET
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1,1
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COMMENTS
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Since there are no squares of the form n^3 + 2, all semiprimes in this sequence are products of distinct primes.
No term in A040034 divides any term in this sequence.
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LINKS
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MATHEMATICA
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Select[Range[100]^3 + 2, PrimeOmega[#] == 2 &] (* Alonso del Arte, Jun 20 2015 *)
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PROG
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(Magma) IsSP:=func<n|&+[d[2]:d in Factorization(n)]eq 2>; [r:n in [1..1000]|IsSP(r) where r is 2+n^3];
(Perl) use ntheory ":all"; my @sp = grep { scalar(factor($_))==2 } map { $_**3+2 } 1..100; say "@sp"; # Dana Jacobsen, Sep 07 2015
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CROSSREFS
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Cf. A237040 (similar sequence with n^3+1).
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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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