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Babai–Seress Conjectures on the Diameter of Finite Groups

**Babai–Seress Conjecture (Conjecture 1.5)**: There exists an absolute constant $C$ such that the diameter of the alternating group $A_n$ satisfies $$\operatorname{diam}(A_n) \leq n^C.$$ *Reference:* [L. Babai and Á. Seress, *On the diameter of permutation groups*, European Journal of Combinatorics 13 (1992), Conjecture 1.5](https://doi.org/10.1016/S0195-6698(05)80029-0) Mathem

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Factorial primes

A factorial prime is a prime that is one more or one less than a factorial. It is conjectured that there are infinitely many factorial primes. There are infinitely many factorial primes. Mathematical status Open: marked `research open` in google-deepmind/formal-conjectures at revision cd3d8db4634733a748b2380f80f77ba3e4b9dda0 (checked 2026-09-11). Formal availability A Prop defi

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Feit-Thompson conjecture on primes

There are no distinct primes $p$ and $q$ such that $\frac{q^p - 1}{q - 1}$ divides $\frac{p^q - 1}{p - 1}$ Mathematical status Open: marked `research open` in google-deepmind/formal-conjectures at revision cd3d8db4634733a748b2380f80f77ba3e4b9dda0 (checked 2026-09-11). Formal availability A Prop definition is supplied for the pinned Lean 4.33.1 environment and must be accepted b

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Congruent Number

A natural number $n$ is called a congruent number if there exists a right triangle with rational sides $a$, $b$, and hypotenuse $c$ such that the area of the triangle is $\frac{1}{2}ab = n$. Tunnell's theorem (sufficient condition assuming BSD) for odd squarefree congruent numbers. Mathematical status Open: marked `research open` in google-deepmind/formal-conjectures at revisio

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Brennan's Conjecture

Brennan's conjecture, part 1: $B(-2) = 1$. Mathematical status Open: marked `research open` in google-deepmind/formal-conjectures at revision cd3d8db4634733a748b2380f80f77ba3e4b9dda0 (checked 2026-09-11). Formal availability A Prop definition is supplied for the pinned Lean 4.33.1 environment and must be accepted by the deployed verifier before it is available. Sources and prov

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Determinantal conjecture

Does the determinant of the sum $A + B$ of two $n \times n$ normal complex matrices $A$ and $B$ always lie in the convex hull of the $n!$ points $\prod\_i (\lambda(A)\_i + \lambda(B)\_{\sigma(i)})$? Here the numbers $\lambda(A)\_i$ and $\lambda(B)\_i$ are the eigenvalues of $A$ and $B$, and $\sigma$ is an element of the symmetric group $S\_n$. Mathematical status Open: marked `

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Fibonacci Primes

There are infinitely many Fibonacci primes, i.e., Fibonacci numbers that are prime It is also a barrier to defining a benchmark from this paper: https://arxiv.org/html/2505.13938v1 (see Figure 8). Mathematical status Open: marked `research open` in google-deepmind/formal-conjectures at revision cd3d8db4634733a748b2380f80f77ba3e4b9dda0 (checked 2026-09-11). Formal availability A

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Beck–Fiala theorem and conjecture

Discrepancy of bounded-degree set systems. Given sets $S_1, \dots, S_m \subseteq [n]$ such that every element of $[n]$ belongs to at most $t$ of the sets (the system has *degree* at most $t$), one seeks a colouring $\chi \colon [n] \to \{-1, +1\}$ making every set as balanced as possible, i.e. minimizing the *discrepancy* $\max_i \left|\sum_{j \in S_i} \chi(j)\right|$. The Beck

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Rudin's conjecture on squares in arithmetic progressions

**Rudin's conjecture.** The maximal number of squares among the first $N$ terms of a non-trivial arithmetic progression grows at most like $\sqrt{N}$: $$Q(N) = O(\sqrt{N}).$$ Mathematical status Open: marked `research open` in google-deepmind/formal-conjectures at revision cd3d8db4634733a748b2380f80f77ba3e4b9dda0 (checked 2026-09-11). Formal availability A Prop definition is su

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Diophantine mm-tuples

A **Diophantine $m$-tuple** is a set of $m$ distinct positive integers $\{a_1, \dots, a_m\}$ such that $a_i a_j + 1$ is a perfect square for every $i \neq j$. The "strong Diophantine 5-tuple conjecture", so-called because it implies the Diophantine 5-tuple theorem (see `noIntegralDiophantineFiveTuple_of_hasUniqueExtensionOfForall`). [Du] Mathematical status Open: marked `resear

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Bloch and Landau constants

Ahlfors and Grunsky also conjectured in [AG37] that this upper bound is the precise value of the Bloch constant. Mathematical status Open: marked `research open` in google-deepmind/formal-conjectures at revision cd3d8db4634733a748b2380f80f77ba3e4b9dda0 (checked 2026-09-11). Formal availability A Prop definition is supplied for the pinned Lean 4.33.1 environment and must be acce

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Brocard's Conjecture

**Brocard's Conjecture** For every `n ≥ 2`, between the squares of the `n`-th and `(n+1)`-th primes, there are at least four prime numbers. Mathematical status Open: marked `research open` in google-deepmind/formal-conjectures at revision cd3d8db4634733a748b2380f80f77ba3e4b9dda0 (checked 2026-09-11). Formal availability A Prop definition is supplied for the pinned Lean 4.33.1 e

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Conjectures about Weakly First Countable spaces

This file formalizes the notion of a weakly first countable topological space and some conjectures around those. Problem 3 in [Ar2013]: Give an example in ZFC of a weakly first- countable compact Hausdorff space which is not first countable. Note: [Ar2013] uses a blanket convention that all spaces are Tychonoff and "compact" means compact Hausdorff. Mathematical status Open: ma

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Tutte's 5-flow conjecture

Let G be a finite bridgeless graph. Does G admit a nowhere-zero 5-flow, i.e. an orientation of its edges together with an integer value f(e) on each edge with 0 < |f(e)| < 5 such that at every vertex the sum of the values on incoming edges equals the sum on outgoing edges? Why it matters Open Problem Garden rates the problem "Outstanding": for planar graphs it follows from flow

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Mean value problem

Given a complex polynomial $p$ of degree $d ≥ 2$ and a complex number $z$ there is a critical point $c$ of $p$, such that $|p(z)-p(c)|/|z-c| ≤ |p'(z)|$. Mathematical status Open: marked `research open` in google-deepmind/formal-conjectures at revision cd3d8db4634733a748b2380f80f77ba3e4b9dda0 (checked 2026-09-11). Formal availability A Prop definition is supplied for the pinned

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Wolstenholme Prime

It is conjectured that there are infinitely many Wolstenholme primes. *Reference:* [Wikipedia](https://en.wikipedia.org/wiki/Wolstenholme_prime#Expected_number_of_Wolstenholme_primes) Mathematical status Open: marked `research open` in google-deepmind/formal-conjectures at revision cd3d8db4634733a748b2380f80f77ba3e4b9dda0 (checked 2026-09-11). Formal availability A Prop definit

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Dubner's conjecture

Every even number greater than 4208 is the sum of two twin primes. Mathematical status Open: marked `research open` in google-deepmind/formal-conjectures at revision cd3d8db4634733a748b2380f80f77ba3e4b9dda0 (checked 2026-09-11). Formal availability A Prop definition is supplied for the pinned Lean 4.33.1 environment and must be accepted by the deployed verifier before it is ava

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*abc* conjecture

For every positive real number `ε`, there exist only finitely many triples `(a, b, c)` of coprime positive integers, with `a + b = c`, such that `c > rad(abc)^(1+ε)` Mathematical status Open: marked `research open` in google-deepmind/formal-conjectures at revision cd3d8db4634733a748b2380f80f77ba3e4b9dda0 (checked 2026-09-11). Formal availability A Prop definition is supplied fo

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Wilson primes

A Wilson prime is a prime $p$ for which $p^2$ divides $(p-1)!+1$. The only known examples are $5$, $13$, and $563$. It is conjectured that infinitely many Wilson primes exist. There are infinitely many Wilson primes. Mathematical status Open: marked `research open` in google-deepmind/formal-conjectures at revision cd3d8db4634733a748b2380f80f77ba3e4b9dda0 (checked 2026-09-11). F

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Kotzig's Conjecture

For any tree $T$ with $n$ edges, the complete graph $K_{2n+1}$ decomposes into $2n+1$ edge-disjoint copies of $T$ via cyclic shifts of a single embedding. The $2n+1$ copies are $f_0, f_1, \dots, f_{2n}$ where $f_i(v) = f_0(v) + i$ for all vertices $v$ — each copy is obtained by adding $i \pmod{2n+1}$ to every vertex of the base copy. This is strictly stronger than `RingelConjec

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