You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-[3-(6-fluoro-9-methylidene-3,10-diazatricyclo[6.4.1.04,13]trideca-1,4,6,8(13)-tetraen-2-yl)phenyl]-N-methylmethanamine into its molecular formula.
user
C20H20FN3
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