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关于正负相间二项式系数倒数级数 被引量:21
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作者 及万会 张来萍 《理论数学》 2012年第4期192-201,共10页
利用已知级数,通过裂项构造出一批新的正负相间二项式系数倒数级数,它们的分母分别含有1到5个奇因子与二项式系数的乘积表达式。所给出正负相间二项式系数倒数级数的和式是封闭形的。并给出正负相间二项式系数数倒数值级数恒等式。裂项... 利用已知级数,通过裂项构造出一批新的正负相间二项式系数倒数级数,它们的分母分别含有1到5个奇因子与二项式系数的乘积表达式。所给出正负相间二项式系数倒数级数的和式是封闭形的。并给出正负相间二项式系数数倒数值级数恒等式。裂项的方法研究二项式系数倒数变换是组合分析的新手段,也是产生新级数的一个初等方法。 展开更多
关键词 二项式系数 裂项 倒数 级数 封闭形 正负相间
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The Series of Reciprocals of Non-central Binomial Coefficients 被引量:5
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作者 Laiping Zhang Wanhui Ji 《American Journal of Computational Mathematics》 2013年第3期31-37,共7页
Utilizing Gamma-Beta function, we can build one series involving reciprocal of non-central binomial coefficients, then We can structure several new series of reciprocals of non-central binomial coefficients by item sp... Utilizing Gamma-Beta function, we can build one series involving reciprocal of non-central binomial coefficients, then We can structure several new series of reciprocals of non-central binomial coefficients by item splitting, these new created denominator of series contain 1 to 4 odd factors of binomial coefficients. As the result of splitting items, some identities of series of numbers values of reciprocals of binomial coefficients are given. The method of splitting terms offered in this paper is a new combinatorial analysis way and elementary method to create new series. 展开更多
关键词 BINOMIAL Coefficients Split Terms reciprocals SERIES Non-central Closed Form
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The Infinite Sum of Reciprocal of the Fibonacci Numbers 被引量:3
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作者 Guo Jie ZHANG 《Journal of Mathematical Research and Exposition》 CSCD 2011年第6期1030-1034,共5页
In this paper,we consider infinite sums of the reciprocals of the Fibonacci numbers.Then applying the floor function to the reciprocals of this sums,we obtain a new identity involving the Fibonacci numbers.
关键词 Fibonacci numbers reciprocals infinite sum elementary method identity.
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Detecting a Regularity in the Generation and Utilization of Primes in the Multiplicative Number Theory 被引量:2
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作者 Silviu Guiasu 《Natural Science》 2019年第6期187-196,共10页
If Goldbach’s conjecture is true, then for each prime number p there is at least one pair of primes symmetric with respect to p and whose sum is 2p. In the multiplicative number theory, covering the positive integers... If Goldbach’s conjecture is true, then for each prime number p there is at least one pair of primes symmetric with respect to p and whose sum is 2p. In the multiplicative number theory, covering the positive integers with primes, during the prime factorization, may be viewed as being the outcome of a parallel system which functions properly if and only if Euler’s formula of the product of the reciprocals of the primes is true. An exact formula for the number of primes less than or equal to an arbitrary bound is given. This formula may be implemented using Wolfram’s computer package Mathematica. 展开更多
关键词 Goldbach’s CONJECTURE Symmetric Prime Cousins Systemic Approach in NUMBER Theory Parallel System Covering INTEGERS with PRIMES Euler’s FORMULA for the Product of reciprocals of PRIMES FORMULA for the Exact NUMBER of PRIMES Less than or Equal to an Arbitrary Bound
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On Approximation by Reciprocals of Spherical Harmonics in L^p Norm 被引量:2
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作者 Bao-huai Sheng 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2005年第4期529-536,共8页
Let S^1-1,q≥2,be the surface of the unit sphere in the Euclidean space R^1,f(x)∈L^p(S^q-1),f(x)≥0,f absohutely unegual to 0,1≤p≤+∞,Then,it is proved in the present paper that there is a spherical harmonic... Let S^1-1,q≥2,be the surface of the unit sphere in the Euclidean space R^1,f(x)∈L^p(S^q-1),f(x)≥0,f absohutely unegual to 0,1≤p≤+∞,Then,it is proved in the present paper that there is a spherical harmonics PN(x) of order≤N and a constant C〉0 such that where ω(f,δ)L^p=sup 0〈t≤δ‖St(f)-f‖L^p is a kind of moduli of continuity and ^‖f-1/PN‖L^p≤Cω(f,N^-1)L^p,St(f,μ)=1/|S^q-2|Sin^2λt ∫-μμ’=t f(μ')dμ' is a translation operator. 展开更多
关键词 Spherical harmonics approximation by reciprocals of polynomials translation operator
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玉米苗期根系相关性状的遗传差异分析 被引量:3
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作者 王芸芸 孙辉 +5 位作者 田涣玲 赵越 张振良 徐扬 李鹏程 徐辰武 《扬州大学学报(农业与生命科学版)》 CAS 北大核心 2020年第2期16-21,共6页
以丹玉13、郑单958、先玉335等玉米品种的10个亲本自交系及其正反交组配的16个杂种F1为试验材料,在水培体系下测定苗期主胚根、种子根和节根的长度、数目、表面积、体积等18个根系性状,研究根系性状之间的相关性以及亲本间、杂交种间、... 以丹玉13、郑单958、先玉335等玉米品种的10个亲本自交系及其正反交组配的16个杂种F1为试验材料,在水培体系下测定苗期主胚根、种子根和节根的长度、数目、表面积、体积等18个根系性状,研究根系性状之间的相关性以及亲本间、杂交种间、亲本对杂交种和正反交F1间根系性状的遗传差异。结果表明:①18个根系性状中,主胚根5个性状间,种子根6个性状间,以及节根7个性状间皆存在显著或极显著正相关,但不同类型的根系性状间相关性较弱。②18个根系性状在供试材料间均存在丰富的变异,其中节根总长、节根体积等性状变异系数较大,主胚根轴根长、种子根平均根长等性状变异系数较小。不同类型根系性状的变异通常表现为节根最大,种子根次之,而主胚根最小。③供试材料间有17个性状存在极显著差异,其中,亲本间有15个性状差异极显著,杂交种间有16个性状差异极显著,亲本对杂交种则有10个性状存在显著或极显著差异,且大多根系性状在杂交种中的表现优于亲本自交系,表现出一定程度的杂种优势。正反交间有12个性状存在显著或极显著差异,说明这些性状可能存在显著的细胞质效应或表观遗传差异。但8个正反交组合的各自测验表明,只有E28×郑58、E28×Mo17 (丹玉13)、郑58×昌7-2 (郑单958)、Mo17×昌7-2和PH6WC×PH4CV (先玉335) 5个杂交组合,在根系性状上可能存在显著的细胞质效应或表观遗传差异。 展开更多
关键词 玉米 苗期 根系性状 正反交 遗传分析
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On the Sum of Reciprocals of Mersenne Primes
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作者 Yoshihiro Tanaka 《American Journal of Computational Mathematics》 2017年第2期145-148,共4页
The sum of reciprocals of Mersenne primes converges to 0.51645417894078856533···, which is an example of a probably infinite subset of primes whose sum of reciprocals is finite and can be computed accur... The sum of reciprocals of Mersenne primes converges to 0.51645417894078856533···, which is an example of a probably infinite subset of primes whose sum of reciprocals is finite and can be computed accurately. This value is larger than , where ?is the set of perfect powers of prime numbers. 展开更多
关键词 Mersenne PRIMES the SUM of reciprocals Unresolved PROBLEM
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Two Kinds of Series Involving the Reciprocals of Binomial Coefficients
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作者 SONG Hai-tao 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期306-310,共5页
By applying the theory of formal power series,the author obtains the closed forms for two kinds of infinite series involving the reciprocals of binomial coefficients,and the author gets another closed form for the inf... By applying the theory of formal power series,the author obtains the closed forms for two kinds of infinite series involving the reciprocals of binomial coefficients,and the author gets another closed form for the infinite series Σr≥m tn+r/(n+rr). 展开更多
关键词 reciprocals of binomial coefficients formal power series combinatorial identity
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Kernel metabolites depict the diversity of relationship between maize hybrids and their parental lines 被引量:1
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作者 Yang Xu Ying Ma +5 位作者 Xin Wang Cheng Li Xuecai Zhang Pengcheng Li Zefeng Yang Chenwu Xu 《The Crop Journal》 SCIE CSCD 2021年第1期181-191,共11页
As the end products of cellular regulatory processes,metabolites provide the link between genotypes and phenotypes.Althoughmetabolites have been widely applied for functional gene detection and phenotype prediction in... As the end products of cellular regulatory processes,metabolites provide the link between genotypes and phenotypes.Althoughmetabolites have been widely applied for functional gene detection and phenotype prediction in maize,there is little research focusing on the genetic information of metabolites per se.Here,we performed genetic analyses for the kernel metabolites of 11 parental inbred lines of six representative maize varieties,including Zhongdan 2,Danyu 13,Yedan 13,Zhengdan 958,Xianyu 355,and Suyu 16,as well as their 26 reciprocal hybrids.We identified a total of 208 metabolites in maize kernels using untargeted metabolite profiling technology.Both cluster analysis and principal component analysis indicated that kernel metabolites could distinguish hybrids from their parents.Analysis of variance further revealed that 163 metabolites exhibited significant differences between parents and hybrids,and 40 metabolites showed significant differences between reciprocal crosses.We also investigated the genetic effects and heterosis for each metabolite.By taking all hybrids into consideration,about two-thirds of all metabolites displayed overdominant with 36.8%and 31%of them displaying positive overdominant and negative overdominant,respectively.Besides,27.5%and 20.4%of all hybrid combinations showed significant mid-parent heterosis and over-parent heterosis,respectively.Our findings revealed that kernel metabolites exhibited the diversity of relationship between maize hybrids and their parental lines.Additionally,we identified 25 significant metabolicmarkers related to 11 agronomic traits using the LASSO method.Seven metabolic markers were associated with more than one trait simultaneously.These results provide a genetic basis for further utilization of metabolites in the genetic improvement of maize. 展开更多
关键词 MAIZE KERNEL METABOLITE reciprocals HETEROSIS
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二项式系数级数连带2个奇数乘积倒数平方和
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作者 及万会 张来萍 《贵阳学院学报(自然科学版)》 2019年第3期18-29,共12页
根据一个已知级数,使用微分-裂项方法得到分母含有1到5个奇偶性不定的线性因子的二项式系数级数连带2个奇数乘积倒数平方和。利用反三角函数与反双曲函数关系给出交错二项式系数倒数级数连带整数倒数平方和。所给出级数的和式是封闭形... 根据一个已知级数,使用微分-裂项方法得到分母含有1到5个奇偶性不定的线性因子的二项式系数级数连带2个奇数乘积倒数平方和。利用反三角函数与反双曲函数关系给出交错二项式系数倒数级数连带整数倒数平方和。所给出级数的和式是封闭形的。并给出二项式系数级数连带2个奇数乘积倒数平方和数值级数恒等式。 展开更多
关键词 二项式系数 2个奇数乘积倒数平方和 微分-裂项 级数
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用“倒数置换法”解积分问题
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作者 王丰 《扬州工业职业技术学院论丛》 2006年第2期71-76,共6页
讨论如何用倒数换元,以解决某些不定积分问题。
关键词 倒数 置换 不定积分问题
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中心型二项式系数倒数级数
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作者 张来萍 杨莉 及万会 《西南民族大学学报(自然科学版)》 CAS 2014年第6期905-915,共11页
利用白塔函数与积分关系将组合数化成积分形式,再用积分公式建立一个二项式系数倒数级数,对这个级数使用裂项方法得到母含有1到5个奇因子的二项式系数倒数级数..并给出二项式系数数倒数值级数恒等式.裂项的方法研究二项式系数倒数变换... 利用白塔函数与积分关系将组合数化成积分形式,再用积分公式建立一个二项式系数倒数级数,对这个级数使用裂项方法得到母含有1到5个奇因子的二项式系数倒数级数..并给出二项式系数数倒数值级数恒等式.裂项的方法研究二项式系数倒数变换是组合分析的新手段,也是产生新级数的一个初等方法. 展开更多
关键词 二项式系数 中心型 倒数 裂项 级数 恒等式.
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Reflexivization and Reciprocality in the Kalabari Language
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作者 Jackrich Oribomate Sopuruchi Christian Aboh 《宏观语言学》 2021年第1期126-133,共8页
This paper examines reflexivization and reciprocality in Kalabari with particular attention to the forms,functions and structures of reflexive and reciprocal constructions(the nominal sub-type)in the language.The pape... This paper examines reflexivization and reciprocality in Kalabari with particular attention to the forms,functions and structures of reflexive and reciprocal constructions(the nominal sub-type)in the language.The paper adopts the binding theory as a framework in analysing the data.The data were gathered through interaction and introspection.The findings reveal that reflexives and reciprocals in Kalabari require a compatible clause-mate antecedent due to the strong anaphoric relationship between reflexive and reciprocal markers and their antecedents respectively.The findings further reveal that the form of Kalabari reflexives consists of-ḇù(-self)and the appropriate form of the pronoun in the language.The paper also reveals that the Kalabari language makes a tripartite distinction for number,person and gender,and the form of the reflexive does not change;only the pronoun changes,while reciprocals consist of a reduplicated form jụmọjụmọ,jápụjápụand jéin jéin.In terms of the structure,findings reveal that reflexives and reciprocals come before the verb of the clause in which they occur.The finding further reveals that reflexives in the language perform both non-emphatic and emphatic functions,while reciprocal relates to human and non-human reference of mutuality.Tonal inflection also makes a distinction in 1st person singular and 2nd person singular reflexives.It is therefore recommended that more studies be done to ascertain the form,function and structure of the verbal and possessive sub-type of reflexive and reciprocal constructions in the language. 展开更多
关键词 REFLEXIVES reciprocals BINDING Kalabari Universal Grammar
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油松双列杂交试验配合力分析 被引量:12
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作者 郭俊荣 杨培华 +1 位作者 谢斌 王亚峰 《西北林学院学报》 CSCD 北大核心 1997年第4期13-18,共6页
对5个油松亲本双列杂交1年生苗高和6年生树高、地径、冠幅的一般配合力、特殊配合力、反交效应及配合力效益值进行测定计算和分析,结果表明,在油松杂交后代中存在着明显的遗传差异。这些差异主要取决于亲本的一般配合力、特殊配合... 对5个油松亲本双列杂交1年生苗高和6年生树高、地径、冠幅的一般配合力、特殊配合力、反交效应及配合力效益值进行测定计算和分析,结果表明,在油松杂交后代中存在着明显的遗传差异。这些差异主要取决于亲本的一般配合力、特殊配合力和反交效应,但一般配合力占优势。并选择出遗传增益较高的两个杂交组合。 展开更多
关键词 油松 双列杂交 配合力 反交效应
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欧拉与自然数平方倒数和 被引量:11
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作者 汪晓勤 《曲阜师范大学学报(自然科学版)》 CAS 2002年第4期29-33,共5页
自然数平方倒数和是 17世纪下半叶的著名数学难题之一 ,它困惑着欧洲当时一流的数学家 .欧拉凭借类比思维方法 ,出人意料地解决了这个难题 .该文对欧拉的几种鲜为人知的方法———幂级数法和“吉拉尔—牛顿公式”
关键词 自然数 平方倒数和 欧拉 伯努利数 幂级数法 吉拉尔--牛顿公式 数学方法 17世纪
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L^p[-1,1](1p<∞)空间中复系数多项式的倒数逼近 被引量:5
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作者 梅雪峰 《工程数学学报》 CSCD 北大核心 2003年第1期111-114,共4页
讨论了Lp[-1,1](1 p<∞)空间函数的复系数多项式的倒数逼近问题,证明了如下结论:设f(x)∈Lp[-1,1](1 p<∞),则存在一个次数不超过3n的复系数多项式Q3n(x)及一个仅与p有关的常数Mp>0使得  f(x)-1Q3n(x)Lp[-1,1] Mpωφ(f,1 n)
关键词 多项式倒数逼近 DITZIAN-TOTIK模 JACKSON型估计 复系数多项式
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多变量追踪研究的模型整合与拓展:考察往复式影响与增长趋势 被引量:5
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作者 刘源 《心理科学进展》 CSSCI CSCD 北大核心 2021年第10期1755-1772,I0001-I0005,共23页
追踪研究当中,交叉滞后模型可以探究多变量之间往复式影响,潜增长模型可以探究个体增长趋势。对两类模型进行整合,例如同时关注往复式影响与个体增长趋势,同时可以定义测量误差、随机截距等变异成分,衍生出随机截距交叉滞后模型、特质−... 追踪研究当中,交叉滞后模型可以探究多变量之间往复式影响,潜增长模型可以探究个体增长趋势。对两类模型进行整合,例如同时关注往复式影响与个体增长趋势,同时可以定义测量误差、随机截距等变异成分,衍生出随机截距交叉滞后模型、特质−状态−误差模型、自回归潜增长模型、结构化残差潜增长模型等。以交叉滞后模型和潜增长模型分别作为基础模型,从个体间/个体内变异分解的角度对上述各类模型梳理,整合出此类模型的分析框架,并拓展建立“因子结构化潜增长模型(factor latent curve model with structured reciprocals)”作为统合框架。通过实证研究(早期儿童的追踪研究−幼儿园版,ECLS-K),建立21049名儿童的阅读和数学能力的往复式影响与增长趋势。研究发现,分离了稳定特质的模型拟合最优。研究也对模型建模思路和模型选择提供了建议。 展开更多
关键词 追踪研究 往复式影响 增长趋势 因子结构化潜增长模型
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一类Orlicz空间中复系数多项式的倒数逼近 被引量:2
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作者 王晓丽 吴嘎日迪 《应用泛函分析学报》 CSCD 2010年第1期71-74,共4页
定义了互余的N函数M(u)和N(v)的Δ条件,并研究了由这种N函数M(u)所生成的一类Orlicz空间中复系数多项式的倒数逼近问题.
关键词 ORLICZ空间 多项式倒数逼近 逼近阶
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多项式的倒数对可微函数的逼近 被引量:2
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作者 余祥明 《南京师大学报(自然科学版)》 CAS CSCD 1989年第3期1-6,共6页
设非线性函数,f(x)∈C[-1,1]是非负的,f′(x)∈C[-1,1],f■(x)=f(x)+ε,其中ε<0,C■是与ε无关的常数,当,f(x)满足[f'(x)]~2/f_■(x)≤C■时,存在次数不超过n的代数多项式P_n(x),使得f(x)-1/P_n(x)1≤C_f~″·1/nω(f′,1/n... 设非线性函数,f(x)∈C[-1,1]是非负的,f′(x)∈C[-1,1],f■(x)=f(x)+ε,其中ε<0,C■是与ε无关的常数,当,f(x)满足[f'(x)]~2/f_■(x)≤C■时,存在次数不超过n的代数多项式P_n(x),使得f(x)-1/P_n(x)1≤C_f~″·1/nω(f′,1/n)(C_f~■仅与C■有关)。根据这个定理,得到多项式f(x)=x^2或x_+~2的倒数的逼近阶是0(2/n^2)。 展开更多
关键词 多项式 倒数 可微函数 逼近
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Orlicz空间内正系数代数多项式倒数对非负连续函数的逼近 被引量:1
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作者 牛彤彤 吴嘎日迪 《数学杂志》 CSCD 北大核心 2014年第1期161-167,共7页
本文研究了Bernstein-Durrmeyer代数多项式倒数对非负连续函数在Orlicz空间中的逼近问题.利用光滑模和K-泛函等工具,获得了收敛速度的估计,所得的结果比Lp空间内的相应结果具有拓展的意义.
关键词 多项式倒数 Bernstein-Durrmeyer多项式算子 ORLICZ空间 逼近
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