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A139440
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Numbers n such that primorial(n)/2 - 4 is prime.
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5
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3, 4, 5, 7, 12, 15, 26, 31, 50, 71, 186, 273, 366, 1542, 1929, 3687, 4407, 15395, 15433
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OFFSET
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1,1
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COMMENTS
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LINKS
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MATHEMATICA
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k = 1; a = {}; Do[k = k*Prime[n]; If[PrimeQ[k - 4], Print[n]; AppendTo[a, n]], {n, 2, 366}]; a
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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