This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A050778 #12 Oct 17 2019 22:54:26
%S A050778 11,17,19,23,29,31,41,47,53,59,71,79,83,89,103,107,109,113,127,131,
%T A050778 149,151,167,179,191,227,229,239,241,251,263,269,271,293,311,313,317,
%U A050778 331,337,359,373,383,401,419,431,439,443,449,461,467,479,491,503,509,521
%N A050778 Primes that are ending primes after the iterated procedure of 'composite added to the sum of its prime factors reaches a prime'.
%e A050778 383 is ending prime for the following composites 182, 204, 218, 226, 228, 254, 329 and 341. For instance 341 (=11*31) -> 341 + (11+31) = 341 + 42 = 383.
%t A050778 a[n_]:=NestWhile[#+Total[Times@@@FactorInteger[#]]&,n,!PrimeQ[#]&]; t={}; Do[If[!PrimeQ[n],AppendTo[t,a[n]]],{n,4,nn=522}]; Select[Union[t],#<nn&] (* _Jayanta Basu_, Jun 01 2013 *)
%Y A050778 Cf. A050779, A050703-A050710.
%K A050778 nonn
%O A050778 1,1
%A A050778 _Patrick De Geest_, Sep 15 1999