Problems
Everything in the archive: the problem as it was posed, what has been attempted against it, and who checked each attempt. The mark down the left of the list says who has looked — a person, a machine, or nobody yet. Human reviews and machine checks are counted separately and are never added together.
33 problems
Do subcubic graphs have exponentially independent sets of linear order?
Are there any other sequences (a_n)_n ∈N of integers appearing 'naturally'with the property that there exists a real α>0 such that (α a_nbmod 2 π)_n=1^∞ has an absolutely continuous non-uniform distribution?
Let G=(V, E) be a locally finite, recurrent graph which is quasi-isometric to R. Let h be a harmonic function on G, and suppose that for some finite cut E(X, Y) separating the two ends of G we have ∂h(X,Y)=0. Then h is either constant or…
Consider maximal planar graphs, 3-connected planar graphs or planar 3-trees. For all such graphs G, is there a constant α<1 and a constant k such that Z(G)≤ α n+k ?
CONJECTURE M(D) : For all A ∈∂ Ω(R_n),f_A(λ)=per(λ A+(1-λ)D_n) is nondecreasing in the interval 0 leqqλ leqq 1 .
I.e., for hereditary property H, what are the maximal properties H' ⊇ H such that d^*(H') = d^*(H)?
Do trees of maximum degree at most 4 have exponentially independent sets of linear order?
If the linear compression dimension of S is given by log_{2}(|S|)+o(n) (hence matches the non-linear compression dimension) then S is contained in the union of 2^{o(n)} translates of some subspaces of size at most |S|.
Let k ≥5 be an odd integer and G be a (n,d,λ) -graph satisfying d^k-1≫ λ^k-2 . Then G has global resilience (1 / 4+o(1)) n d with respect to being C_k -free.
An interesting question is whether every red-blue coloring of a k-pseudorandom graph contains a monochromatic path of length \Omega(\frac{n}{\sqrt{k}}).
It is not known whether there is a finite k-chromatic graph of girth at least g and with \chi_{c}^{s}(G)=2k.
We conjecture that uniqueness of the MCB implies U ≠ ∅.
Does there exist a graph Γ of order n and level of symmetry equal to n-k/n for arbitrarily large k ≥2 ?