Lebesgue constants for some interpolational ${\mathcal L}$-splines

We find exact values for the uniform Lebesgue constants of interpolational ${\mathcal L}$-splines that are bounded on the real axis, have equidistant knots, and correspond to the linear third-order differential operator ${\mathcal L}_{3}(D)=D(D^{2}+\alpha^{2})$ with constant real coefficients, where $\alpha>0$. We compare the obtained result with the Lebesgue constants of other ${\mathcal L}$-splines.