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A087227
Number of distinct prime factors of A087226(n), the LCM of terms in trajectory of 3x+1 (function) initiated at n.
1
0, 1, 3, 1, 2, 3, 6, 1, 7, 2, 5, 3, 3, 6, 6, 1, 4, 7, 7, 2, 3, 5, 5, 3, 7, 3, 37, 6, 6, 6, 35, 1, 8, 4, 4, 7, 7, 7, 12, 2, 36, 3, 8, 5, 5, 5, 35, 3, 7, 7, 8, 3, 3, 37, 35, 6, 10, 6, 11, 6, 6, 35, 36, 1, 7, 8, 9, 4, 5, 4, 34, 7, 36, 7, 5, 7, 7, 12, 12, 2, 7, 36, 35, 3, 3, 8, 11, 5, 10, 5, 32, 5, 6, 35, 35
OFFSET
1,3
COMMENTS
This sequence differs from A078719: a(n) <= (number of odd terms in list).
EXAMPLE
n=25: A087226(25) = 535792400 with factor-set={2,5,11,13,17,19,29} so a(25)=7, while number of odd terms in the trajectory is A078219(25)=8.
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Aug 28 2003
STATUS
approved