cp's OEIS Frontend

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.

A050777 First occurrence from iterated procedure 'composite k added to sum of its prime factors reaches a prime' yielding n skipped primes.

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%I A050777 #11 Oct 17 2019 22:42:33
%S A050777 38400,6,10,26,8,18,4,39,16,30,27,32,126,76,92,87,63,77,122,49,62,120,
%T A050777 56,50,45,117,110,196,88,102,75,246,171,72,70,234,60,469,66,217,260,
%U A050777 198,244,387,550,230,528,362,519,764,500,494,566,376,548,386,526,481
%N A050777 First occurrence from iterated procedure 'composite k added to sum of its prime factors reaches a prime' yielding n skipped primes.
%H A050777 C. Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_066.htm">Puzzle 66 - The SOPF sequences</a>
%e A050777 a(1)=38400 + (2+2+2+2+2+2+2+2+2+3+5+5) = 38431. '0' primes between 38400 and 38431.
%e A050777 a(2)=6 + (2+3) = 11. '1' prime between 6 and 11.
%e A050777 a(3)=10 + (2+5) = 17. '2' primes between 10 and 17.
%t A050777 a[n_]:=Length[Select[Range[n+1,NestWhile[#+Total[Times@@@FactorInteger[#]]&,n,!PrimeQ[#]&]-1],PrimeQ]]; t={38400}; Do[i=4; While[a[i]!=k,If[PrimeQ[i+1],i+=2,i++]]; AppendTo[t,i],{k,57}]; t (* _Jayanta Basu_, Jun 01 2013 *)
%Y A050777 Cf. A050765, A050768-A050776, A050703.
%K A050777 nonn
%O A050777 0,1
%A A050777 _Patrick De Geest_, Sep 15 1999