Approximation of the lateral distribution function of the Cherenkov light from extensive air showers in the primary energy region 1-100 PeV

The approximation function that makes it possible to describe the lateral distribution function of Cherenkov light of individual extensive air showers from various primary nuclei with energies of 1-100 PeV and zenith angles up to 20 degrees with an accuracy better than 5\% in the distance range 0-500 meters from the shower axis was found. Initially the approximation was intended for processing the events of the SPHERE-2 experiment, but its can also be applied to any experiment that uses the spatial distribution function at the level of the Earth's surface. A comparison was made with a simpler approximating function used in the SPHERE-2 processing and with the function used by the TAIGA experiment.