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A071771
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Least k > 0 such that the nextprime(k*primorial(n)) - k*primorial(n) is composite.
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0
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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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For a(2): the second primorial (A002110) is 6. It is not until k = 413, or 6*413 = 2478, that the next prime > 2478 = 2503 less 2478 which equals 25 is a composite.
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MATHEMATICA
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Do[p = Product[ Prime[i], {i, 1, n}]; k = 1; While[ q = NextPrim[k*p] - k*p; q == 1 || PrimeQ[q], k++ ]; Print[k], {n, 1, 6}]
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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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