maths.free › Combinatorics & Graph Theory › The Many Faces of Combinatorics › Arithmetic Combinatorics
Arithmetic Combinatorics
In recent years, a great deal of attention has been focused on topics in arithmetic combinatorics, with a number of deep and exciting discoveries in the offing.
Arithmetic Combinatorics
In recent years, a great deal of attention has been focused on topics in arithmetic combinatorics, with a number of deep and exciting discoveries in the offing. In some sense, this area is closely aligned with Ramsey theory and number theory, but recent work shows connections with real and complex analysis, as well. Furthermore, the roots of arithmetic combinatorics go back many years. In this section, we present a brief overview of this rich and rapidly changing area.
Recall that an increasing sequence \(a_1\lt a_2\lt a_3\lt \dots\lt a_t)\) of integers is called an arithmetic progression when there exists a positive integer \(d\) for which \(a_{i+1}-a_i=d\), for all \(i=1,2,\dots,t-1\). The integer \(t\) is called the length of the arithmetic progression.
Material will be added here.
现在轮到你 没有计算器能解决这一个问题, 但其中的碎片是可以计算的。 请在下面尝试一个, 或者输入您自己的 。
此处所用符号
输入完整定义、图片和其中每个字母的含义的符号。
人们对人们提出的问题
Permutation or combination?
Ask whether order matters. A lock code is a permutation (order matters); a hand of cards is a combination (it does not).
What is a graph in this sense?
Dots (vertices) joined by lines (edges), not a plot. Road maps, social networks and molecules are graphs; questions like "is there a route" and "how few colours" are graph theory.
本页部分内容从 Keller & Trotter, Applied Combinatorics (CC BY-SA 4.0). 在这里进行浓缩和重新解释;错误属于我们。
更多 Combinatorics & Graph Theory
The counting principlesPigeonhole principle and inclusion, exclusionBinomial coefficients and Pascal's triangleRecurrences and generating functionsGraphs: vertices, edges, degreesPaths, cycles, trees, Euler and HamiltonColouring and planar graphs