18-Jun-1995
Unsolved Problem 25:
Start with any positive integer. Halve it if it is even;
triple it and add 1 if it is odd. If you keep repeating
this procedure, must you eventually reach the number 1?
For example, starting with the number 6, we get:
6, 3, 10, 5, 16, 8, 4, 2, 1.
Reference:
- [Gardner 1983]
- Martin Gardner,
Wheels, Life, and Other Mathematical Amusements.
W. H. Freeman. New York: 1983.
Page 196.
The Collatz Conjecture
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