ABSTRACT: In this note, we first derive an exponential generating function of the alternating run polynomials. We then deduce an explicit formula of the alternating run polynomials in terms of the ...

EMBED (for Archive.org item Description fields) [archiveorg github.com-halfrost-LeetCode-Go_-_2022-10-18_22-50-31 width=560 height=384 frameborder=0 ...

* https://leetcode-cn.com/problems/permutation-sequence/solution/hui-su-jian-zhi-python-dai-ma-java-dai-ma-by-liwei/ class Solution2 { 直接用回溯法做的话 ...

> - Given *n* will be between 1 and 9 inclusive. > - Given *k* will be between 1 and *n*! inclusive.