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1194 of 1194 statement records

17 source collections · 43 mathematical fields

Source labels openPapers · Combinatorics

Monochromatic quantum graphs (inherited vertex colorings)

For N=6N = 6 and D=4D = 4, does there exist no solution to the monochromatic quantum graph equation system over C\mathbb{C}?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openErdős Problems · Number theory

Erdős Problem 647

Let τ(n)\tau(n) count the number of divisors of nn. Is there some n>24n > 24 such that

maxm<n(m+τ(m))n+2? \max_{m < n}(m + \tau(m)) \leq n + 2?
Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · Combinatorics

Monochromatic quantum graphs (inherited vertex colorings)

For N=6N = 6 and D=5D = 5, does there exist no solution to the monochromatic quantum graph equation system over C\mathbb{C}?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openErdős Problems · Number theory

Erdős Problem 647: Lim

Erdős says 'it is extremely doubtful' that there are infinitely many such nn, and in fact suggests that

limnmaxm<n(τ(m)+mn)=. lim_{n\to\infty} \max_{m < n}(\tau(m) + m − n) = \infty.
Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · Combinatorics

Monochromatic quantum graphs (inherited vertex colorings)

For N=6N = 6 and all D3D \geq 3, does there exist no solution to the monochromatic quantum graph equation system over C\mathbb{C}?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openErdős Problems · Number theory

Erdős Problem 647: Infinite

Erdős says it 'seems certain' that for every kk there are infinitely many nn for which

maxnk<m<n(m+τ(m))n+2. \max_{n−k < m < n}(m + \tau(m)) ≤ n + 2.
Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · Combinatorics

Monochromatic quantum graphs (inherited vertex colorings)

For N=8N = 8 and D=3D = 3, does there exist no solution to the monochromatic quantum graph equation system over C\mathbb{C}?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openErdős Problems · Number theory

Erdős Problem 66

Is there and ANA \subset \mathbb{N} is such that limn1A1A(n)logn\lim_{n\to \infty}\frac{1_A\ast 1_A(n)}{\log n} exists and is 0\ne 0?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · Combinatorics

Monochromatic quantum graphs (inherited vertex colorings)

For N=10N = 10 and D=3D = 3, does there exist no solution to the monochromatic quantum graph equation system over C\mathbb{C}?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openErdős Problems · Number theory

Erdős Problem 672

Can the product of an arithmetic progression of positive integers n,n+d,...,n+(k1)dn, n + d, ..., n + (k - 1)d of length ≥ 4, with (n,d)=1(n, d) = 1, be a perfect power?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · Combinatorics

Monochromatic quantum graphs (inherited vertex colorings)

For N=10N = 10 and D=4D = 4, does there exist no solution to the monochromatic quantum graph equation system over C\mathbb{C}?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openErdős Problems · Number theory

Erdős Problem 677

Denote by M(n,k)M(n, k) the least common multiple of the finite set {n+1,,n+k}\{n+1, \dotsc, n+k\}. Is it true that for all mn+km \geq n + k, we get M(m,k)M(n,k)M(m, k) \neq M(n, k)?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · Combinatorics

Monochromatic quantum graphs (inherited vertex colorings)

For N=10N = 10 and D=5D = 5, does there exist no solution to the monochromatic quantum graph equation system over C\mathbb{C}?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openErdős Problems · Number theory

Erdős Problem 68

Is n=21n!1\sum_{n=2}^\infty \frac{1}{n!-1} irrational?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · Combinatorics

Monochromatic quantum graphs (inherited vertex colorings)

For N=10N = 10 and D=6D = 6, does there exist no solution to the monochromatic quantum graph equation system over C\mathbb{C}?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openErdős Problems · Number theory

Erdős Problem 680: I

Is it true that, for all sufficiently large nn, there exists some kk such that

p(n+k)>k2+1,p(n+k)>k^2+1,

where p(m)p(m) denotes the least prime factor of mm?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · Combinatorics

Monochromatic quantum graphs (inherited vertex colorings)

For N=10N = 10 and D=7D = 7, does there exist no solution to the monochromatic quantum graph equation system over C\mathbb{C}?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openErdős Problems · Number theory

Erdős Problem 680: Ii

Can one prove this is false if we replace k2+1k^2+1 by e(1+ϵ)k+Cϵe^{(1+\epsilon)\sqrt{k}}+C_\epsilon, for all ϵ>0\epsilon>0, where Cϵ>0C_\epsilon>0 is some constant?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openPapers · Combinatorics

Monochromatic quantum graphs (inherited vertex colorings)

For N=10N = 10 and D=8D = 8, does there exist no solution to the monochromatic quantum graph equation system over C\mathbb{C}?

Source checked Jul 26, 20261 pinned Lean statementInspect problem
Source labels openErdős Problems · Number theory

Erdős Problem 681

Erdős problem 681.* Is it true that for all large nn there exists kk such that n+kn + k is composite and p(n+k)>k2p(n+k) > k^2, where p(m)p(m) is the least prime factor of mm ?

Source checked Jul 26, 20261 pinned Lean statementInspect problem