Collatz step

collatzStepdef

One Collatz step: halve an even number, or triple an odd one and add one.

def collatzStep (n : ℕ) : ℕ := if n % 2 = 0 then n / 2 else 3 * n + 1

Used by

Collatz reachability

From Mathlib

Data.Nat.Notation

import Conjectura.Defs.Mathematics.NumberTheory.CollatzStep · maintainer — open · raw source

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