You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 5,10,15-tris(1-octylpyridin-1-ium-2-yl)-20-(1-octylpyridin-2-ylidene)-21H-porphyrin into molecular formula.
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C72H93N8+3
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