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A240545
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Least k > 0 such that n + p(k) is prime, where p(k) is the number of partitions of k.
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2
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2, 1, 1, 2, 1, 2, 1, 8, 3, 2, 1, 2, 1, 9, 3, 2, 1, 2, 1, 8, 3, 2, 1, 9, 4, 8, 3, 2, 1, 2, 1, 8, 4, 11, 3, 2, 1, 8, 3, 2, 1, 2, 1, 9, 3, 2, 1, 10, 4, 8, 3, 2, 1, 9, 4, 10, 3, 2, 1, 2, 1, 8, 4, 15, 3, 2, 1, 8, 3, 2, 1, 2, 1, 9, 4, 8, 3, 2, 1, 8, 3, 2
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OFFSET
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0,1
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COMMENTS
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Conjecture of Zhi-Wei Sun: a(n) < n for n > 7.
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LINKS
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EXAMPLE
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a(7)=8 because k=8 is the smallest k such that 7+A000041(k) is prime.
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MATHEMATICA
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a[n_] := For[k = 1, True, k++, If[PrimeQ[n + PartitionsP[k]], Return[k]]];
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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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