A186188 Least k such that A156077^(k)(n)=1 where a^(k)=a(a^(k-1)).

1, 1, 1, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6

Offset

1,4

References

B. Cloitre, Experimental evidence for the Keane's conjecture, preprint 2011

Links

Table of n, a(n) for n=1..86.

Formula

conjecture: a(n)=floor(log(n)/log(2))+0 or +1

Prog

(PARI) a(n)=if(n<0, 0, t=n; c=1; while(A156077(t)>1, t=A156077(t); c++); c)

Crossrefs

Cf. A000002, A156077.

Sequence in context: A130255 A082527 A294235 * A227177 A132944 A210568

Adjacent sequences: A186185 A186186 A186187 * A186189 A186190 A186191

Keyword

nonn

Author

Benoit Cloitre, Feb 14 2011

Status

approved