You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[2-[(17Z,20Z)-octacosa-17,20-dienoyl]oxy-3-[(Z)-tridec-9-enoyl]oxypropyl] (18Z,21Z,24Z)-dotriaconta-18,21,24-trienoate is the IUPAC name of a molecule. Please give its molecular formula.
user
C76H136O6
assistant