Results 71 to 80 of about 144,275 (215)
Australas. J Comb., 2020 JENGA, a very popular game of physical skill, when played by perfect players, can be seen as a pure combinatorial ruleset. Taking that into account, it is possible to play with more than one tower; a move is made by choosing one of the towers, removing a block from there, that is, a disjunctive sum.
Carvalho, Alda +2 more
openaire +1 more source
On Strongly and Robustly Critical Graphs
Journal of Graph Theory, EarlyView.ABSTRACT In extremal combinatorics, it is common to focus on structures that are minimal with respect to a certain property. In particular, critical and list‐critical graphs occupy a prominent place in graph coloring theory. Stiebitz, Tuza, and Voigt introduced strongly critical graphs, i.e., graphs that are k $k$‐critical yet L $L$‐colorable with ...
Anton Bernshteyn +3 more
wiley +1 more source
Teaching of probability theory and combinatorics at secondary schools
Lietuvos Matematikos Rinkinys, 2004 The topics of probability theory and combinatorics were brought into curricula of Lithuanian secondary schools ten years ago. The problems of teaching and actual situation of apprehension of concepts of probability theory and combinatorics are analyzed.
Eugenijus Stankus
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A simple recurrence formula for the number of rooted maps on surfaces by edges and genus [PDF]
Discrete Mathematics & Theoretical Computer Science, 2014 We establish a simple recurrence formula for the number $Q_g^n$ of rooted orientable maps counted by edges and genus. The formula is a consequence of the KP equation for the generating function of bipartite maps, coupled with a Tutte equation, and it was
Sean Carrell, Guillaume Chapuy
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On Tight Tree‐Complete Hypergraph Ramsey Numbers
Journal of Graph Theory, EarlyView.ABSTRACT Chvátal showed that for any tree T $T$ with k $k$ edges, the Ramsey number R ( T , n ) = k ( n − 1 ) + 1 $R(T,n)=k(n-1)+1$. For r = 3 $r=3$ or 4, we show that, if T $T$ is an r $r$‐uniform nontrivial tight tree, then the hypergraph Ramsey number R ( T , n ) = Θ ( n r − 1 ) $R(T,n)={\rm{\Theta }}({n}^{r-1})$.
Jiaxi Nie
wiley +1 more source
Orientations of Graphs With at Most One Directed Path Between Every Pair of Vertices
Journal of Graph Theory, EarlyView.ABSTRACT Given a graph G $G$, we say that an orientation D $D$ of G $G$ is a KT orientation if, for all u , v ∈ V ( D ) $u,v\in V(D)$, there is at most one directed path (in any direction) between u $u$ and v $v$. Graphs that admit such orientations have been used to construct graphs with large chromatic number and small clique number that served as ...
Barbora Dohnalová +3 more
wiley +1 more source
Continuous dependence and differentiation of solutions of finite difference equations
International Journal of Mathematics and Mathematical Sciences, 1991 Conditions are given for the continuity and differentiability of solutions of initial value problems and boundary value problems for the nth order finite difference equation, u(m+n)=f(m,u(m),u(m+1),…,u(m+n−1)),m∈ℤ.
Johnny Henderson, Linda Lee
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On the Hardness of Switching to a Small Number of Edges
Journal of Graph Theory, EarlyView.ABSTRACT Seidel's switching is a graph operation which makes a given vertex adjacent to precisely those vertices to which it was non‐adjacent before, while keeping the rest of the graph unchanged. Two graphs are called switching‐equivalent if one can be made isomorphic to the other one by a sequence of switches. Jelínková et al. [DMTCS 13, no. 2, 2011]
Vít Jelínek +2 more
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Creativity and Innovation Management, EarlyView.ABSTRACT This paper explores the limits of mission‐directed entrepreneurial states by drawing on the theory of recombinant innovation and F.A. Hayek's insights on the spontaneous growth of knowledge in society. First, the use of discretionary policymaking curtails the range of knowledge generated in the process of social interaction, limiting the scope
Bryan Cheang, Praharsh Mehrotra
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Graphs with 4-Rainbow Index 3 and n − 1
Discussiones Mathematicae Graph Theory, 2015 Let G be a nontrivial connected graph with an edge-coloring c : E(G) → {1, 2, . . . , q}, q ∈ ℕ, where adjacent edges may be colored the same. A tree T in G is called a rainbow tree if no two edges of T receive the same color. For a vertex set S ⊆ V (G),
Li Xueliang +3 more
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