You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[4-(1H-indol-3-yl)-3,6-dihydro-2H-pyridin-1-yl]-(5-propyl-1H-pyrazol-3-yl)methanone is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H22N4O
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