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A050768
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Iterated procedure 'composite k added to sum of its prime factors reaches a prime' yields 1 skipped prime.
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1
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6, 20, 48, 112, 320, 1326, 1400, 4165, 4374, 10395, 12852, 15827, 20412, 23232, 24300, 24990, 25000, 27200, 27300, 31407, 33660, 34965, 38480, 41553, 42525, 50688, 53508, 65450, 66000, 68400, 69498
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OFFSET
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0,1
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LINKS
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EXAMPLE
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a(2)=20 + (2+2+5) = ending prime 29. Between 20 and 29 lies exactly one prime 23.
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MATHEMATICA
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aQ[n_]:=NextPrime[NestWhile[#+Total[Times@@@FactorInteger[#]]&, n, !PrimeQ[#]&], -1]==NextPrime[n]; Select[Range[70000], !PrimeQ[#]&&aQ[#]&] (* Jayanta Basu, May 31 2013 *)
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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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