115
Voted
EJC
2016
10 years 1 months ago
2016
The maximum drop size of a permutation π of [n] = {1, 2, . . . , n} is defined to be the maximum value of i − π(i). Chung, Claesson, Dukes and Graham found polynomials Pk(x) ...
125
Voted
EJC
2016
10 years 1 months ago
2016
A finite word is u is said to be bordered if u has a proper prefix which is also a suffix of u, and unbordered otherwise. Ehrenfeucht and Silberger proved that an infinite word...
117
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EJC
2016
10 years 1 months ago
2016
We continue to explore cyclotomic factors in the descent set polynomial Qn(t), which was introduced by Chebikin, Ehrenborg, Pylyavskyy and Readdy. We obtain large classes of facto...
133
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EJC
2016
10 years 1 months ago
2016
We study “positive” graphs that have a nonnegative homomorphism number into every edge-weighted graph (where the edgeweights may be negative). We conjecture that all positive ...
113
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EJC
2016
10 years 1 months ago
2016
The well known dichotomy conjecture of Feder and Vardi states that for every family Γ of constraints CSP(Γ) is either polynomially solvable or NP-hard. Bulatov and Jeavons reform...