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Composite n added to sum of its prime factors is nextprime(n).
5

%I #26 Oct 14 2017 14:11:16

%S 38400,59290,89700,93639,155952,356400,682080,1226907,1468320,1648640,

%T 2592000,2995200,3595500,3933644,5845203,5967360,8860995,8953560,

%U 9748480,11351340,12819224,13226976,13712490,16193520,18375000,19294436,21206016,25259520,28297500

%N Composite n added to sum of its prime factors is nextprime(n).

%H Donovan Johnson and Giovanni Resta, <a href="/A050765/b050765.txt">Table of n, a(n) for n = 1..1033</a> (terms < 10^12, first 500 terms from Donovan Johnson)

%H C. Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_066.htm">See also related puzzle</a>

%e nextprime(93639) = 93639 + (3+7+7+7+7+13) = 93683.

%t Reap[For[n = 4, n <= 2*10^7, n = If[PrimeQ[n+1], n+2, n+1], If[n + Total[Times @@@ FactorInteger[n] ] == NextPrime[n], Print[n]; Sow[n]]]][[2, 1]] (* _Jean-François Alcover_, Oct 18 2013 *)

%t cspfQ[n_]:=CompositeQ[n]&&NextPrime[n]==n+Total[Flatten[Table[ #[[1]], #[[2]]] &/@FactorInteger[n]]]; Select[Range[29*10^6],cspfQ] (* _Harvey P. Dale_, Oct 14 2017 *)

%Y Cf. A050766, A050703, A050710, A105779, A235425.

%K nonn,nice

%O 1,1

%A _Patrick De Geest_, Sep 15 1999

%E Offset corrected by _Donovan Johnson_, Oct 18 2013