You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-(5-methyl-1H-1,2,4-triazol-3-yl)-1,3,4,9-tetrahydropyrido[3,4-b]indole-2-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C15H16N6O
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