|
%I #5 Mar 30 2012 18:39:21
%S 0,2,3,4,4,4,5,5,5,5,6,6,6,6,7,7,6,7,7,7,7,7,7,7,7,7,8,8,8,8,8,8,8,8,
%T 8,8,8,8,8,8,8,8,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,
%U 9,9,9,9,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10
%N Least k such that S^k(n)=n^2 where S(x)=n*ceiling(sqrt(x)).
%C For all m>k, S^m(n)=n^2
%F a(n)=sqrt(n)+o(sqrt(n))
%o (PARI) a(n)=if(n<0,0,z=1; c=0; while(abs(z-n^2)>0,z=n*ceil(sqrt(z)); c++); c)
%K nonn
%O 0,2
%A _Benoit Cloitre_, Oct 07 2003
|
