摘要：In the present paper, using the discrete analogue of the operator $\mathrm{d} ^{6}/\mathrm{d} x^{6}-1$, we construct an interpolation spline that minimizes the quantity $\int _(^)(\varphi {'''}(x)+\varphi (x))^,\,\mathrm{d}x$ in the Hilbert space $W_,^{(3,0)}$. We obtain explicit formulas for the coefficients of the interpolation spline. The obtained interpolation spline is exact for the exponential-trigonometric functions ${{e}^{-x}}$, ${{e}^{\frac{x},}}\cos ( \frac{\sqrt"},x)$, and ${{e}^{\frac{x},}}\sin ( \frac{\sqrt"},x )$.
