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Number Theory Open

Collatz Conjecture

Starting from any positive integer, repeatedly apply n → n/2 if even and n → 3n + 1 if odd. Does every trajectory eventually reach 1?

Impact
72 /100
Funded
$6,100
Donors
245
Of goal
51%

Why this matters

Collatz is famously easy to state and stubbornly hard to prove. It is a proving ground for new ideas about iterative maps, reverse trees, and probabilistic heuristics on the integers.

What a solution unlocks

  • New machinery for simple-looking arithmetic dynamics
  • Transferable tools for other 3x+1-type maps
  • Clearer limits of current proof techniques

Downstream impact

Even partial structural theorems have historically seeded ideas in ergodic theory and computer-assisted proof — a full resolution would be a landmark of elementary-looking mathematics.

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