You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2E)-2-[4,5-bis(ethenyl)-3-methylidene-1H-pyrrol-2-ylidene]-1H-indol-3-one;ethane;molecular hydrogen The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H30N2O
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