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131.
刘建军 《内蒙古师范大学学报(自然科学版)》2005,34(1):116-119
阐述了历史上错位排问题最早出现的两种不同形式及其发展历程.论述了由解决此问题而引出的数学中的重要方法与原理——递推方法和容斥原理.介绍了数学家们研究由错位排问题延伸出的经典数学名题“夫妻入座问题”的成果. 相似文献
132.
Austen Curtin Christine Austin Alessandro Giuliani Manuel Ruiz Marín Francheska Merced-Nieves Martha M. Tllez-Rojo Robert O. Wright Manish Arora Paul Curtin 《Entropy (Basel, Switzerland)》2021,23(12)
Metabolism and physiology frequently follow non-linear rhythmic patterns which are reflected in concepts of homeostasis and circadian rhythms, yet few biomarkers are studied as dynamical systems. For instance, healthy human development depends on the assimilation and metabolism of essential elements, often accompanied by exposures to non-essential elements which may be toxic. In this study, we applied laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) to reconstruct longitudinal exposure profiles of essential and non-essential elements throughout prenatal and early post-natal development. We applied cross-recurrence quantification analysis (CRQA) to characterize dynamics involved in elemental integration, and to construct a graph-theory based analysis of elemental metabolism. Our findings show how exposure to lead, a well-characterized toxicant, perturbs the metabolism of essential elements. In particular, our findings indicate that high levels of lead exposure dysregulate global aspects of metabolic network connectivity. For example, the magnitude of each element’s degree was increased in children exposed to high lead levels. Similarly, high lead exposure yielded discrete effects on specific essential elements, particularly zinc and magnesium, which showed reduced network metrics compared to other elements. In sum, this approach presents a new, systems-based perspective on the dynamics involved in elemental metabolism during critical periods of human development. 相似文献
133.
Recurrence formulas for overlap, nuclear attraction, and electron-repulsion integrals over Laguerre Gaussian-type functions are presented. They have been derived using compact recurrence relations for homogeneous solid spherical harmonic operators but are rather lengthy as compared to those over Cartesian Gaussian-type functions. © 1998 John Wiley & Sons, Inc. Int J Quant Chem 66 : 273–279, 1998 相似文献
134.
也谈厄米多项式的递推关系 总被引:2,自引:1,他引:1
由厄米多项式的母函数出发,推导出厄米多项式的递推关系以及厄米多项式中系数的递推关系. 相似文献
135.
136.
高福山 《吉林大学学报(信息科学版)》2005,23(1):64-68
针对计算机病毒的自我复制特性目前尚未有普遍认可的数学模型的问题,从病毒模型结构出发,分析了病毒自我复制特性,指出病毒自我复制的本质是一系列关系的映射,是代码的线性序结构.提出由本原函数代入及递归变换,通过递归规则,解释病毒的自复制为函数的自引用、递归自再生过程.突出了应用数学形式体系研究的无矛盾性、数理逻辑相关的理论和方法. 相似文献
137.
随机环境中马氏链的常返性和瞬时性 总被引:1,自引:0,他引:1
讨论了随机环境马氏链中具有强π不可约性链的常返性的判定,从而得到了强π不可约链常返性判定的充分必要条件,同时给出了在一定条件下随机环境中的马氏链的瞬时性判定的几个充分条件. 相似文献
138.
The aim of this work is to give some criteria on the convergence of vector valued continued fractions defined by Samelson inverse. We give a new approach to prove the convergence theory of continued fractions. First, by means of the modified classical backward recurrence relation, we obtain a formula between the m-th and n-th convergence of vector valued continued fractions. Second, using this formula, we give necessary and sufficient conditions for the convergence of vector valued continued fractions. 相似文献
139.
Jorge M. V. Capela Marisa V. Capela Clóvis A. Ribeiro 《Journal of mathematical chemistry》2009,45(3):769-775
The aim of this work is to find approaches for the Arrhenius integral by using the n-th convergent of the Jacobi fractions. The n-th convergent is a rational function whose numerator and denominator are polynomials which can be easily computed from three-term
recurrence relations. It is noticed that such approaches are equivalent to the one established by the Gauss quadrature formula
and it can be seen that the coefficients in the quadrature formula can be given as a function of the coefficients in the recurrence
relations. An analysis of the relative error percentages in the approximations is also presented. 相似文献
140.
Larry Ericksen 《Mathematica Slovaca》2009,59(3):261-274
The divisibility of numbers is obtained by iteration of the weighted sum of their integer digits. Then evaluation of the related
congruences yields information about the primality of numbers in certain recursive sequences. From the row elements in generalized
Delannoy triangles, we can verify the primality of any constellation of numbers. When a number set is not a prime constellation,
we can identify factors of their composite numbers. The constellation primality test is proven in all generality, and examples
are given for twin primes, prime triplets, and Sophie Germain primes.
相似文献