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A267507
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Prime numbers n such that n-1 is squarefree and all prime divisors of n-1 other than 19 are in the sequence.
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5
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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S[1] = {2, 19}; PR[S_] := Product[S[[i]], {i, Length[S]}];
S[m_] := S[m] = Union[S[m - 1], Select[Table[PR[Subsets[S[m - 1]] [[i]]] + 1, {i, 2^Length[S[m - 1]]}], PrimeQ]]; A267507 = Complement[S[7], {19}]
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CROSSREFS
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KEYWORD
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nonn,fini,full
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AUTHOR
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STATUS
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approved
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