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 A050768 Iterated procedure 'composite k added to sum of its prime factors reaches a prime' yields 1 skipped prime. 1
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS EXAMPLE a(2)=20 + (2+2+5) = ending prime 29. Between 20 and 29 lies exactly one prime 23. MATHEMATICA aQ[n_]:=NextPrime[NestWhile[#+Total[Times@@@FactorInteger[#]]&, n, !PrimeQ[#]&], -1]==NextPrime[n]; Select[Range[70000], !PrimeQ[#]&&aQ[#]&] (* Jayanta Basu, May 31 2013 *) CROSSREFS Cf. A050703, A050710. Sequence in context: A011928 A055455 A203552 * A161438 A063488 A299292 Adjacent sequences:  A050765 A050766 A050767 * A050769 A050770 A050771 KEYWORD nonn AUTHOR Patrick De Geest, Sep 15 1999. STATUS approved

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Last modified January 15 19:17 EST 2019. Contains 319171 sequences. (Running on oeis4.)