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A086567
Length of cycle produced by the function f: (x; y; z) ->(x-y-z; y; 2*y + z) if y + = z <x and (x; y; z) ->(y + z -x; x; 2*x -z) if y +z >x when started at (n,1,1).
1
1, 0, 3, 5, 4, 0, 5, 10, 7, 11, 6, 0, 7, 16, 11, 9, 10, 21, 8, 0, 9, 21, 12, 27, 11, 14, 17, 23, 10, 0, 11, 32, 18, 27, 18, 13, 15, 28, 19, 32, 12, 0, 13, 38, 25, 19, 18, 47, 15, 44, 16, 38, 18, 50, 14, 0, 15, 39, 20, 59, 18, 54, 28, 17, 24, 31, 21, 28, 29, 49, 16, 0, 17
OFFSET
1,3
FORMULA
a(k^2 + k) = 0, a(k^2 + k - 1) = 2*k, a(k^2 + k + 1) = a(k^2) = 2*k + 1
EXAMPLE
a(5) = 4 because (5; 1; 1) -> (3; 1; 3) -> (1; 3; 3) -> (5; 1; = -1) -> (5; 1; 1) : length of cycle =4.
CROSSREFS
Cf. A087855.
Sequence in context: A096822 A195383 A303069 * A016611 A198619 A168223
KEYWORD
nonn
AUTHOR
Philippe Deléham, Sep 24 2003
STATUS
approved