Interactive mathematics

Collatz Tree

Start from 1 and explore which numbers can flow back to it.

The Collatz rule sends an even number to n/2 and an odd number to 3n+1. This page runs the question backwards: for a number n, which numbers could have arrived at n in one step? The 1→4→2→1 loop is pruned so the result stays a readable tree, not a proof of the conjecture.

Fork ruleEvery node has the even reverse predecessor 2n. A second odd predecessor exists only when n ≡ 4 mod 6, except that the 4→1 reverse edge is omitted to remove the root cycle.

Visualization only: this does not prove the Collatz conjecture.Click a node to inspect its forward path.

Tree depth: 10

Labels

29 nodes · 28 edges

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