On the Cardinal Spline Interpolation Corresponding to Infinite Order Differential Operators

<正> This paper discusses some problems on the cardinal spline interpolation correspond-ing to infinite order differential operators.The remainder formulas and a dual theorem are es-tablished for some convolution classes,where the kernels are PF densities.Moreover,the exacterror of approximation of a convolution class with interpolation cardinal splines is determined.The exact values of average n-Kolmogorov widths are obtained for the convolution class.