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Ending primes for n-th composite number in the iterated procedure of composite added to sum of prime factors.
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%I #12 Jul 16 2015 22:32:32

%S 23,11,23,23,17,19,23,23,47,41,29,31,47,47,47,41,71,71,71,83,47,53,47,

%T 71,59,71,71,83,59,167,71,59,149,167,71,167,83,71,167,79,89,251,167,

%U 149,149,83,269,89,167,251,251,113,239,149,167,109,127,269,251,107

%N Ending primes for n-th composite number in the iterated procedure of composite added to sum of prime factors.

%C If we consider nonprimes instead of composite then a(1)=2. Sorted list of primes generated here are given in A050778.

%e For the first composite number 4 repeated application of composite added to sum of prime factors give 4, 8, 14, 23 and so a(1)=23.

%t a[n_] := NestWhile[#+Total[Times@@@FactorInteger[#]]&, n, !PrimeQ[#]&]; t={}; Do[If[!PrimeQ[n], AppendTo[t, a[n]]], {n, 4, 80}]; t

%Y Cf. A050703-A050710, A050778.

%K nonn

%O 1,1

%A _Jayanta Basu_, May 31 2013