The 3x+371 Conjecture

The iterates y, t(y), t(t(y)),... of the 3x+371 function

t(x) = x/2 if x is even,
t(x) = (3x+371)/2 if x is odd,

are printed and the number of steps taken to reach one of the integers 721, 371, 265, 25, 0, -371, -563, -1855, -6307, is recorded.

It is conjectured (by Keith Matthews) that every trajectory starting from a non-zero integer will end in one of the numbers in this list and subsequently cycle. (The cycle lengths are printed in bold type.):

Enter M:

Last modified 15th May 2010
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