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A081882
Number of steps needed to reach an integer starting with n-1/4 and iterating the map x ->x*ceiling(x).
0
2, 8, 1, 2, 3, 2, 1, 4, 2, 3, 1, 4, 8, 3, 1, 4, 2, 4, 1, 2, 3, 2, 1, 5, 2, 5, 1, 3, 4, 6, 1, 8, 2, 5, 1, 2, 3, 2, 1, 3, 2, 6, 1, 5, 5, 3, 1, 3, 2, 3, 1, 2, 3, 2, 1, 8, 2, 7, 1, 3, 4, 4, 1, 4, 2, 4, 1, 2, 3, 2, 1, 5, 2, 3, 1, 4, 6, 3, 1, 5, 2, 8, 1, 2, 3, 2, 1, 6, 2, 4, 1, 3, 4, 5, 1, 4, 2, 4, 1, 2, 3, 2, 1, 3, 2
OFFSET
2,1
FORMULA
It seems that sum(k=2, n, a(k)) is asymptotic to 3n
PROG
(PARI) a(n)=if(n<0, 0, s=n-1/4; c=0; while(frac(s)>0, s=s*ceil(s); c++); c)
CROSSREFS
Cf. A068119.
Sequence in context: A024544 A202539 A197287 * A242070 A155694 A200689
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Apr 13 2003
STATUS
approved