On the construction, for the functions si x and $\Phi (x) = (2/\sqrt \pi )\int\limits_0^x {e^{ - t2} dt}$, of polynomials which approximate them almost as well as the best approximations
English version (Springer): Ukrainian Mathematical Journal 26 (1974), no. 2, pp 177-185.
Citation Example: Stolyarchuk V. K. On the construction, for the functions si x and $\Phi (x) = (2/\sqrt \pi )\int\limits_0^x {e^{ - t2} dt}$, of polynomials which approximate them almost as well as the best approximations // Ukr. Mat. Zh. - 1974. - 26, № 2. - pp. 216–226.
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