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A186189
Least k such that A074286^(k)(n) = 1 where a^(k) = a(a^(k-1)).
0
1, 1, 2, 2, 2, 3, 3, 3, 3, 3, 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, 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, 6, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7
OFFSET
1,3
REFERENCES
Benoit Cloitre, Experimental evidence for the Keane's conjecture, preprint 2011
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(A074286(t)>1, t=A074286(t); c++); c)
CROSSREFS
Cf. A074286.
Sequence in context: A130239 A091092 A218461 * A083375 A088519 A135034
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Feb 14 2011
STATUS
approved