You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 3,9-dimethyl-7-pentyl-4,5a-dihydro-1H-purino[8,7-c][1,2,4]triazin-5-ium-6,8-dione into its molecular formula.
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C14H21N6O2+
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