You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance [(4aS,8aR)-4a-(cyclobutylmethoxymethyl)-3,4,5,7,8,8a-hexahydro-2H-pyrano[3,2-c]pyridin-6-yl]-pyridin-4-ylmethanone .
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C20H28N2O3
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