You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named [2-[(Z)-docos-13-enoyl]oxy-3-octadecanoyloxypropyl] (19Z,22Z,25Z,28Z,31Z)-tetratriaconta-19,22,25,28,31-pentaenoate by IUPAC nomenclature, provide its molecular formula.
user
C77H138O6
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