直交投影与最小二乘问题

本文介绍一个计算直交投影的递推公式，并介绍如何用其求解线性最小二乘问题。     

p-级数(p为偶数)求和的递推公式

运用付里叶级数推导p-级数sum from n=1 to∞1/n~p(p为偶数)求和的递推公式,运用递推公式计算sum from n=1 to∞1/n~p1(p=2,4,6,8,10,12)的和.     

一种基于能量的RNA二级结构预测的动态划分算法

预测单链RNA分子序列的二级结构是计算生物学中的一个重要内容.本文基于RNA分子结构的稳定性原理.提出了一种预测RNA二级结构的新算法——基于能量的动态划分算法.该算法的空间复杂度仅为O(n),时间复杂度近似为O(n2·logn),且预测结构有较好的精度.     

组合计数的群论与计算机方法

本文综述组合数学和图论中解决计数问题的群论与计算机方法及其最新发展。传统的计数方法得到有限的计数公式或递推公式等，然而许多复杂的问题很难得到有限的表达式，即使能得到，公式也往往非常复杂。由于计算机技术的发展不仅使复杂的计数公式有了实际意义，而且可以设计恰当的计算方法进行数值计算，使计数问题有更为广阔的发展领域。另一方面，为了计算不同构的图或组合结构，最有效的方法是群论方法，因此把群论方法与计算机方     

高阶Bernoulli数的递推公式

本文得到了高阶 Bernoulli数的若干递推公式 ,这些公式不仅结构精美 ,递推关系鲜明 ,而且便于应用     

计算一批锁具总数的快速算法

本讨论了94年全国大学生数学建模竞赛B题“锁具装箱问题”中关于一批锁具个数的求解问题．给出了计算一批锁具个数的递推公式，应用该递推公式，可以快速求出具有任意i个槽的一批锁具的个数．     

保费随机的离散风险模型的罚金期望函数

本文把经典的复合二项风险模型进行推广,其中保费收取方式不再是时间的线性函数而是一个二项过程.我们把它的罚金期望看成初始资本的函数,得到了罚金期望函数的递推公式和渐近估计,最后利用罚金期望函数的递推公式和渐近估计给出了几个重要的破产量的递推公式及其渐近估计.     

Bautin焦点量公式的简单推导

本文对二次系统Ｂａｕｔｉｎ焦点量Ｖ３，Ｖ５，Ｖ７的表达式进行了重新推导，并且纠正了Ｖ７，表达式中的错误。由于应用了计算焦占量的一类新的递推公式，使推导过程简洁明了，避免了以往推尼它们时所表现出的复杂性。     

关于Sk=1+2k+3k+…+nk的探究

1.递推公式由二项展开式得对i求和上式左边可化为(n+1)k+1-1+Sk+1,从而有(1)由(1)式得递推公式     

含有根式的递推数列问题求解策略

某些含有根式的递推数列问题，用三角代换法使其根式脱去非常奏效，即借助于同角三角函数的平方关系式sin^2α＋cos^2α=1、1＋tan^2α=secα、1＋cot^2α=csc^2α以及倍角公式，将已知递推数列问题转化为角成等比数列问题，进而使问题迅速获解．观察递推公式的根式结构待征，选择恰当的三角函数将通项代换是解决问题的关键．     

Darboux transformations and recursion operators for differential-difference equations

We review two concepts directly related to the Lax representations of integrable systems: Darboux transformations and recursion operators. We present an extensive list of integrable differential-difference equations with their Hamiltonian structures, recursion operators, nontrivial generalized symmetries, and Darboux-Lax representations. The new results include multi-Hamiltonian structures and recursion operators for integrable Volterra-type equations and integrable discretizations of derivative nonlinear Schrödinger equations such as the Kaup-Newell, Chen-Lee-Liu, and Ablowitz-Ramani-Segur (Gerdjikov-Ivanov) lattices. We also compute the weakly nonlocal inverse recursion operators.     

A note on constrained M-estimation and its recursive analog in multivariate linear regression models

In this paper, the constrained M-estimation of the regression coefficients and scatter parameters in a general multivariate linear regression model is considered. Since the constrained M-estimation is not easy to compute, an up-dating recursion procedure is proposed to simplify the computation of the estimators when a new observation is obtained. We show that, under mild conditions, the recursion estimates are strongly consistent. In addition, the asymptotic normality of the recursive constrained M-estimators of regression coefficients is established. A Monte Carlo simulation study of the recursion estimates is also provided. Besides, robustness and asymptotic behavior of constrained M-estimators are briefly discussed. The research was supported by the Natural Sciences and Engineering Research Council of Canada     

二维递归序列的渐近性

In this paper, we give precise formulas for the general two-dimensional recursion sequences by generating function method, and make use of the multivariate generating functions asymptotic estimation technique to compute their asymptotic values.     

一类平面多项式微分系统赤道环量的代数递推公式

本文研究一类形式相当一般的平面多项式系统赤道环量(Gauss球面的无穷远点奇点量)的计算,建立了系统赤道环量计算的简明的线性代数递推公式.应用递推公式计算赤道环量,只需用系统系数做四则运算,避免了通常计算赤道环量需要的复杂的积分运算和解方程,极易用计算机代数系统作符号推导并且不含舍入误差.     

Asymptotics on Two-dimensional Recursion Sequences

In this paper, we give precise formulas for the general two-dimensional recursion sequences by generating function method, and make use of the multivariate generating functions asymptotic estimation technique to compute their asymptotic values.     

A block Cholesky-LU-based QR factorization for rectangular matrices

The Householder method provides a stable algorithm to compute the full QR factorization of a general matrix. The standard version of the algorithm uses a sequence of orthogonal reflections to transform the matrix into upper triangular form column by column. In order to exploit (level 3 BLAS or structured matrix) computational advantages for block-partitioned algorithms, we develop a block algorithm for the QR factorization. It is based on a well-known block version of the Householder method which recursively divides a matrix columnwise into two smaller matrices. However, instead of continuing the recursion down to single matrix columns, we introduce a novel way to compute the QR factors in implicit Householder representation for a larger block of several matrix columns, that is, we start the recursion at a block level instead of a single column. Numerical experiments illustrate to what extent the novel approach trades some of the stability of Householder's method for the computational efficiency of block methods.     

Analysis of a class of dynamic programming models for multi-stage uncertain systems

Uncertainty theory is a new branch of mathematics concerned with the analysis of subjective indeterminacy. This paper deals with the optimal control problem for a multi-stage dynamic system in an indeterminate environment. Firstly, we formulate a practical uncertain control model based on the critical value criterion and present recursion equations for this model based on Bellman’s Principle. A special linear model is shown to illustrate how the recursion equations operate to obtain the analytical solution. Furthermore, we demonstrate a hybrid intelligent algorithm to evaluate and approximate the optimal solutions of more general cases. Finally, a discrete version of the production-inventory problem is discussed and numerically analyzed to illuminate the effectiveness of the methodology.     

Numerical algorithms for Panjer recursion by applying Bernstein approximation

In actuarial science, Panjer recursion (1981) is used in insurance to compute the loss distribution of the compound risk models. When the severity distribution is continuous with density function, numerical calculation for the compound distribution by applying Panjer recursion will involve an approximation of the integration. In order to simplify the numerical algorithms, we apply Bernstein approximation for the continuous severity distribution function and obtain approximated recursive equations, which are used for computing the approximated values of the compound distribution. The theoretical error bound for the approximation is also obtained. Numerical results show that our algorithm provides reliable results.     

RNA secondary structure, permutations, and statistics

We construct a permutation representation for RNA secondary structure. We also introduce some basic combinatorial statistics for RNA secondary structure and relate them to permutation statistics when appropriate. These statistics allow us to quantify some structural phenomena in RNA secondary structure.     

A Generalized Topological Recursion for Arbitrary Ramification

The Eynard–Orantin topological recursion relies on the geometry of a Riemann surface S and two meromorphic functions x and y on S. To formulate the recursion, one must assume that x has only simple ramification points. In this paper, we propose a generalized topological recursion that is valid for x with arbitrary ramification. We justify our proposal by studying degenerations of Riemann surfaces. We check in various examples that our generalized recursion is compatible with invariance of the free energies under the transformation ${(x, y) \mapsto (y, x)}$ , where either x or y (or both) have higher order ramification, and that it satisfies some of the most important properties of the original recursion. Along the way, we show that invariance under ${(x, y) \mapsto (y, x)}$ is in fact more subtle than expected; we show that there exists a number of counterexamples, already in the case of the original Eynard–Orantin recursion, that deserve further study.