You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-[5-methyl-4-[1-[2-[1-(3-nitrophenyl)ethylidene]hydrazinyl]ethenyl]triazol-1-yl]-1,2,5-oxadiazol-3-amine is the IUPAC name of a molecule. Please give its molecular formula.
user
C15H15N9O3
assistant