The diagonal generalized Collatz conjecture

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For p≥0p\geq0, let (dp,αp,βp)+=(2p+1,3⋅2p,2p)+(d_p,\alpha_p,\beta_p)_+=(2^{p+1},3\cdot2^p,2^p)_+ and let TpT_p be its associated mapping. Diagonal generalized Collatz conjecture. If p≥0p\geq0 and p≠2p\neq2, the triplet is strongly admissible of order one, with unique cycle

Ω(1)=(1→2→22→⋯→2p+1→1),\Omega(1)=(1\to2\to2^2\to\cdots\to2^{p+1}\to1),

of length p+2p+2, and every n≥1n\geq1 satisfies Tp(k)(n)=1T_p^{(k)}(n)=1 for some k≥0k\geq0. For p=2p=2, the triplet (8,12,4)+(8,12,4)_+ is strongly admissible of order two, with cycles Ω(1)=(1→2→4→8→1)\Omega(1)=(1\to2\to4\to8\to1) and Ω(67)=(67→102→156→236→356→536→67)\Omega(67)=(67\to102\to156\to236\to356\to536\to67), and every n≥1n\geq1 satisfies T2(k)(n)∈{1,67}T_2^{(k)}(n)\in\{1,67\} for some k≥0k\geq0. This is a special case of the generalized conjecture above and includes the classical Collatz mapping when p=0p=0; the paper offers computational support but no proof.

References

Primary source

Abderrahman Bouhamidi, “An Extension of the Collatz Conjecture modulo 2^p+2^q”, arXiv:2601.06208 (2026).

Progress summary

Refreshed
Open

No proof or counterexample has appeared; only finite computer experiments support the predicted behavior.

The conjecture, formulated by Abderrahman Bouhamidi in January 2026, predicts that every trajectory in this generalized Collatz family reaches the specified cycle or cycles. It includes the classical case p=0p=0.

Known results

  • Bouhamidi reports tests for 0≤p≤250\leq p\leq25 and initial values n≤107n\leq10^7, supporting the predicted cycles but proving nothing exhaustive.
  • For the broader family, additional large finite checks are reported, including a case with p=3p=3 and q=1q=1; these do not establish the diagonal conjecture.

January 2026 computational study

Bouhamidi’s paper states the diagonal assertions as conjectures and explicitly offers numerical support rather than a proof. No retrieved source reports a counterexample, proof, independent verification, withdrawal, or retraction.

Current status (as of October 2026): The conjecture remains open; only finite computational support is recorded, including the classical case p=0p=0.

Sources

Solutions 0

No solutions have been posted yet.