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131.
We discuss a family of restricted m-ary overpartition functions bm,j (n), which is the number of m-ary overpartitions of n with at most i + j copies of the non-overlined part m^i allowed, and obtain a family of congruences for bm,lm-1 (n). 相似文献
132.
We mainly consider the existence and asymptotic behavior of positive solutions of the following system
133.
Bao-Xuan Zhu 《Discrete Mathematics》2013,313(22):2602-2606
134.
135.
单圈偶图是边数等于顶点数的简单连通偶图.Δ(G)表示图G的最大度.文中给出了最大度为Δ(≥n+1/2)的n阶单圈偶图的谱半径的上界,并刻画了达到该上界的图.文中还证明了当Δ(G)≥[(2n+1)/3]+1时,n(≥8)阶单圈偶图G的谱半径随着最大度的递增而严格递增,并在此基础上给出了谱半径排在前17位的n(≥16)阶单圈偶图. 相似文献
136.
By combined power evolution laws of the spectral parameter and the initial constants of integration,a new differential-difference hierarchy is presented from the Toda spectral problem.The hierarchy contains the classic Toda lattice equation,the nonisospectral Toda lattice equation and the mixed Toda lattice equation as reduced cases.The evolution of the scattering data in the inverse scattering transform is analyzed in detail and exact soliton solutions are computed through the corresponding inverse scattering transform. 相似文献
137.
In this paper, the compatibility between the gauge transformations and the additional symmetry of the constrained discrete Kadomtsev-Petviashvili hierarchy is given, which preserves the form of the additional symmetry of the cdKP hierarchy, up to shifting of the corresponding additional flows by ordinary time flows. 相似文献
138.
In this paper, a Volterra model with mutual interference and time delays is investigated. By applying the comparison theorem of the differential equations and constructing a suitable Lyapunov functional, sufficient conditions which guarantee the permanence and existence of a unique globally attractive positive almost periodic solution of the system are obtained. Two suitable examples together with their numeric simulations are given to illustrate our results by using MatLab. 相似文献
139.
We give a criterion for the log-convexity (resp. the strong q -log-convexity) of the first column of certain infinite triangular array (An,k)0?k?n of nonnegative numbers (resp. of polynomials in q with nonnegative coefficients), for which the recurrence relation is of the form This allows a unified treatment of the log-convexity of the Catalan-like numbers, as well as that of the q-log-convexity of some classical polynomials. In particular, we obtain simple proofs of the q-log-convexity of Narayana polynomials. 相似文献
An,k=fkAn−1,k−1+gkAn−1,k+hkAn−1,k+1.
140.
《Electrochemistry communications》2002,4(3):205-209
The electrochemical properties of 0.95LiMn0.5Ni0.5O2·0.05Li2TiO3 have been investigated as part of a study of xLiMO2·(1−x)Li2M′O3 electrode systems for lithium batteries in which M=Co, Ni, Mn and M′=Ti, Zr, Mn. The data indicate that the electrochemically inactive Li2TiO3 component contributes to the stabilization of LiMn0.5Ni0.5O2 electrodes, which improves the coulombic efficiency of Li/xLiMn0.5Ni0.5O2·(1−x)Li2TiO3 cells for x<1. The 0.95LiMn0.5Ni0.5O2·0.05Li2TiO3 electrodes provide a rechargeable capacity of approximately 175 mAh/g at 50 °C when cycled between 4.6 and 2.5 V; there is no indication of spinel formation during electrochemical cycling. 相似文献