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6180 of 221 problems
  • Erdős Problem #1153Paul Erdős, Paul Turán, 1961

    VibeMathed records no statement for this problem. See erdosproblems.com for the original.

    Analysissolved

    1 attempt · 1 machine check

  • Is the closest vector problem NP-hard to approximate within polynomial factors n^c? Yes for some c > 0: hardness of approximation reaches polynomial factors, with consequences for decoding and related lattice problems - a foundational…

    Theoretical computer sciencecandidate

    1 attempt · 1 machine check

  • In the circle of Kummer's regular primes and Vandiver's conjecture, the paper proves that almost all primes are partially regular, yielding a partial Vandiver theorem for a density-one set of primes, with consequences for Kubota-Leopoldt…

    Number theorysolved

    1 attempt · 1 machine check

  • Erdős Problem #42Paul Erdős, 1995

    VibeMathed records no statement for this problem. See erdosproblems.com for the original.

    Number theorysolved

    1 attempt · 1 machine check

  • Erdős Problem #650Paul Erdős, 1995

    VibeMathed records no statement for this problem. See erdosproblems.com for the original.

    Number theorysolved

    1 attempt · 1 machine check

  • Grothendieck asked whether every finite locally free group scheme of order n is killed by n (its n-th convolution power map equals the unit). The counterexample is an order-4 group scheme not killed by 4 (killed only by 8); since Deligne…

    Algebradisproved

    1 attempt · 1 machine check

  • Erdős Problem #671Paul Erdős, 1982

    For triangular arrays of nodes a_i^n∈[-1,1] let L^nf be the Lagrange interpolation polynomials of a continuous f, with fundamental polynomials p_i^n. Is there a choice of nodes such that for every continuous f there is some x where…

    Analysiscandidate

    1 attempt · 1 machine check

  • Erdős Problem #106Paul Erdős, 1932

    If f(n) is the maximum total side length of n interior-disjoint squares packed in the unit square, is f(k^2 + 1) = k? An exact rational configuration packs 17 squares with total side length greater than 4, refuting the identity at k = 4.

    Geometry & topologycandidate

    1 attempt · 1 machine check

  • Huang, Jiang and Oblomkov conjectured that the Eulerian q-series counting commuting pairs of nilpotent matrices with X^a = Y^b equals an explicit theta-and-eta product, making the point count essentially modular. The conjecture is layered…

    Number theorypartial

    1 attempt · 1 machine check

  • The Target-Free Clique Conjecture for Threshold-Linear NetworksCarina Curto, Jesse Geneson, Katherine Morrison, 2019

    The target-free clique conjecture asserts that the supports of stable fixed points of a nondegenerate combinatorial threshold-linear network are exactly its target-free cliques, the bidirected cliques no outside vertex receives an edge…

    Combinatoricsdisproved

    1 attempt · 1 machine check

  • Does the middle-third Cantor measure admit a Fourier frame, that is, a countable set of exponentials giving two-sided frame bounds on its L^2 space? No. The Cantor measure with base b admits no Fourier frame for any odd integer b > 1,…

    Analysisdisproved

    1 attempt · 1 machine check

  • If Sidon sets A, B ⊆ 1, …, N satisfy (A-A) ∩ (B-B) = 0, must binom|A|2 + binom|B|2 ≤ binomf(N)2 + O(1), where f(N) is the largest Sidon-set size in [N] - and can the bound be improved by a fixed proportion when |A| = |B|?

    Number theorydisproved

    1 attempt · 1 machine check

  • Wegner conjectured in 1965 that every finite family R of axis-parallel rectangles satisfies τ(R) ≤ 2ν(R) - 1, where τ is the minimum number of piercing points and ν the largest pairwise-disjoint subfamily. False, by an explicit…

    Geometry & topologydisproved

    1 attempt · 1 machine check

  • Litvak conjectured in 2018 that for every p > 0 the quantity E[min_i ≤ n |g_i|^p], for g ~ N(0,Σ), is minimized over n × n correlation matrices by the Gram matrix of the regular simplex in R^n-1. False: the matrix Σ^cos_ij = cos(π(i-j)/n)…

    Probability & statisticsdisproved

    1 attempt · 1 machine check

  • Sendov's ConjectureBlagovest Sendov, 1959

    Let p be a complex polynomial of degree n ≥ 2 whose zeros all lie in the closed unit disk. Then for every zero a of p, there exists a critical point ζ of p such that |ζ-a| ≤ 1. This is the standard Sendov statement and exactly matches the…

    Analysissolved

    1 attempt · 1 machine check

  • Erdős Problem #1091Paul Erdős, 1976

    VibeMathed records no statement for this problem. See erdosproblems.com for the original.

    Combinatoricssolved

    1 attempt · 1 machine check

  • Erdős Problem #1202Paul Erdős, 1980

    VibeMathed records no statement for this problem. See erdosproblems.com for the original.

    Number theorysolved

    1 attempt · 1 machine check

  • A generalization of Boppana's entropy inequality, of the kind used in union-closed-sets arguments, proved and formalized: the sharp form with the extremal constant characterized via the unique positive solution of an explicit equation.

    Combinatoricssolved

    1 attempt · 1 machine check

  • For the switch-walk-switch walk on Z_2 wr Z started at (0,0) and (0,2), prove |P_t^x - P_t^y|_TV asymp t^-1/2.

    Probability & statisticssolved

    1 attempt · 1 machine check

  • VibeMathed records no statement for this problem. See erdosproblems.com for the original.

    Number theorydisproved

    1 attempt · 1 machine check