You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-(1H-benzimidazol-2-yl)-1,2,3,3a,4,5,6,6a-octahydrocyclopenta[c]pyrrole-3-carboxamide into its molecular formula.
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C15H18N4O
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