You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[3-[(8Z,11Z,14Z)-heptadeca-8,11,14-trienoyl]oxy-2-[(11Z,13Z,15Z)-octadeca-11,13,15-trienoyl]oxypropyl] (4Z,7Z,10Z,13Z,16Z)-nonadeca-4,7,10,13,16-pentaenoate is the IUPAC name of a molecule. Please give its molecular formula.
user
C57H88O6
assistant