1 Results A recursion formula to the solutions of a class of linear ordinary differential equations with constant coefficients is given.

2 Taking advantage of the recursion formula, the number-, weight-and Z-average molecular weight of polymers can be caculated without difficulty.

3 A simple recursion formula can then be used to solve such a system.

4 Two formulae: the recursion formula and the general formula obtained by mathematical induction were given.

5 The method is simple and efficient. A recursion formula to calculate the effective load at the boundary is presented.

6 The recursion formula for calculating WOB are established by means of the mechanical analysis.

7 In this paper a simplified recursion formula of discretization orthogonal polynomial in the case of uniform step is presented.

8 However, the use of convolution model is to deduce recursion formula of the reflection for the converted wave.

9 The essential of studying the forward and inverse problems of converted wave with the use of convolution model is to deduce recursion formula of the reflection coefficient.

10 Finally, the article also produced in the collection value information similar relations in the processing incomplete information utilization, and derived its recursion formula.

11 The article gives the reversible condition of a kind of jump Vandermonde matrix through linear equations, and recursion formula and the expression of its inverse Matrix.

12 In this paper, for a discrete time risk model with random rates of interest, we obtain the recursion formula of the duration of ruin's probability.

13 By translating this real cubic system into a complex planar system, an applicable linear algebraic recursion formula of the equator and the first 6 quantities of the equator are given.

14 The author has solved the transport equation by using the double power scattering cross section proposed recently, and derived the recursion formula for moments of the ion range distribution.