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 A110157 #11 Aug 14 2013 19:12:58 %S A110157 0,1,2,3,2,3,4,5,2,3,4,5,4,5,6,7,2,3,4,5,4,5,6,7,4,3,4,3,6,7,8,9,2,3, %T A110157 4,5,4,5,6,7,4,5,6,7,6,7,8,9,4,5,4,5,4,5,4,5,6,7,8,9,8,9,10,5,2,3,4,5, %U A110157 4,5,6,7,4,5,6,7,6,7,8,9,4,3,4,5,6,7,8,9,6,7,8,9,8,9,10,11,4,5,6,3,4,5,6,7 %N A110157 a(n) = a(rad(n) - 1) + 1, where rad(n) is the squarefree kernel of n, rad=A007947. %C A110157 a(n) = a(A075423(n)) + 1; %C A110157 a(A075426(n)) = n+1 and a(m) < n+1 for m < A075426(n). %H A110157 Reinhard Zumkeller, <a href="/A110157/b110157.txt">Table of n, a(n) for n = 0..10000</a> %F A110157 a(n) < 4 log_2(n) for n > 1. - _Charles R Greathouse IV_, Aug 08 2013 %o A110157 (PARI) rad(n)=my(f=factor(n)[,1]);prod(i=1,#f,f[i]) %o A110157 a(n)=if(n<4,n,1+a(rad(n)-1)) \\ _Charles R Greathouse IV_, Aug 08 2013 %o A110157 (Haskell) %o A110157 a110157 n = genericIndex a110157_list (n-1) %o A110157 a110157_list = 0 : map ((+ 1) . a110157 . (+ 1)) a075423_list %o A110157 -- _Reinhard Zumkeller_, Aug 14 2013 %K A110157 nonn %O A110157 0,3 %A A110157 _Reinhard Zumkeller_, Jul 14 2005