f 0 = 1 2 π 1 L ( 1 C 0 + 1 C 1 + 1 C 2 ) . {\displaystyle f_{0}={1 \over 2\pi }{\sqrt {{1 \over L}\left({1 \over C_{0}}+{1 \over C_{1}}+{1 \over C_{2}}\right)}}\ .}
Wikipedia has related information at Clapp oscilator
