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arXiv · 1706.08399

There are no cycles in the $3n+1$ sequence

Ivan Slapnicar
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Abstract

In 1937, Lothar Collatz conjectured that the sequence generated by the rule $f(n)=3n+1$ for $n\in\mathbb{N}$ odd, $f(n)=n/2$ for $n\in\mathbb{N}$ even, starting in any positive integer $n$ produces $1$. This is equivalent to (1) there are no cycles except the trivial one, (1-4-2-1), and (2) there is no infinite sequence. We prove (1) using graph theory and linear algebra.

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Ivan Slapnicar. 2017-06-20. There are no cycles in the $3n+1$ sequence. https://arxiv.org/abs/1706.08399

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