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 A064918 #9 Jun 19 2018 05:15:11 %S A064918 0,0,1,0,2,0,1,1,3,0,1,0,2,1,2,0,4,0,1,2,2,0,1,2,3,1,2,0,3,0,1,1,5,1, %T A064918 1,0,2,2,3,0,3,0,1,1,2,0,3,1,4,1,2,0,3,2,1,3,4,0,1,0,2,1,2,1,6,0,2,3, %U A064918 2,0,1,0,3,2,3,1,4,0,1,1,4,0,1,3,2,1,2,0,3,1,1,2,4,1,2,0,5,2,2,0,3,0,1,1,4 %N A064918 a(n) is the number of iterations of k -> A064916(k) to reach a prime, starting at n. %C A064918 a(p) = 0 for all primes p. %H A064918 Harry J. Smith, <a href="/A064918/b064918.txt">Table of n, a(n) for n = 2..1000</a> %e A064918 a(6) = 2 as A064916(A064916(6)) = A064916(4) = 3 = A064917(6). %o A064918 (PARI) lpf(n)= { local(f); f=factor(n); return(f[1, 1]) } { for (n=2, 1000, m=n; a=0; while (!isprime(m), L=lpf(m); m=m / L + L - 1; a++); write("b064918.txt", n, " ", a) ) } \\ _Harry J. Smith_, Sep 29 2009 %Y A064918 Cf. A064916, A064917, A064922. %K A064918 nonn %O A064918 2,5 %A A064918 _Reinhard Zumkeller_, Oct 14 2001