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It is shown, that the function $$\begin{array}{cc}\hfill H\left(x\right)& =\sum _{k=-\infty }^{\infty }{e}^{-k^{2}x}\hfill \\ \multicolumn{2}{c}{\text{satisfies}\text{the}\text{relation}}\\ \hfill H\left(x\right)& =\sum _{n=0}^{\infty }\frac{{\left(2\pi \right)}^{2n}}{\left(2n\right)!}{H}^{\left(n\right)}\left(x\right).\hfill \end{array}$$