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A063256
Let f be a function on rationals p/q (p,q coprime) defined by f(p/q) = abs(p-q)/g(p), where g(p) is the next odd number (starting with p) that we get after iteration of h(n) = n/2 when n is even, 3n-1 when n is odd. Start with f(n/1) and iterate f until it reaches again an integer, which is a(n). If no integer is reached, then a(n)=0.
2
0, 1, 2, 3, 3, 5, 2, 7, 5, 9, 10, 8, 1, 9, 4, 15, 9, 17, 2, 2, 6, 15, 2, 2, 9, 7, 23, 4, 3, 15, 3, 31, 17, 33, 27, 2, 2, 4, 2, 5, 15, 21, 42, 32, 5, 33, 12, 11, 7, 1, 4, 2, 11, 5, 5, 1, 15, 3, 17, 4, 7, 33, 5, 63, 33, 65, 53, 2, 3, 2, 3, 11, 4, 45, 2, 8, 9, 3, 11, 2, 21, 3, 9, 2, 22, 63, 11, 8
OFFSET
1,3
EXAMPLE
We get 14/1 -> 13/7 -> 6/19 -> 13/3 -> 10/19 -> 9/5 -> 4/13 -> 9/1 so a(14)=9.
CROSSREFS
KEYWORD
nonn
AUTHOR
Floor van Lamoen, Jul 12 2001
STATUS
approved