\[\boxed{\mathbf{661}.}\]
\[1)\ y = {0,4}^{x};\]
\[2)\ y = \left( \sqrt{2} \right)^{x};\]
\[3)\ y = \left( \frac{1}{\sqrt{2}} \right)^{x};\]
\[4)\ y = \left( \sqrt{3} \right)^{x};\]