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What is the molecular formula of the molecule 12,12,13,13-tetramethyl-9-(trideuteriomethyl)-8,10,17-triazapentacyclo[9.6.2.02,7.08,19.014,18]nonadeca-1(17),2,4,6,9,11(19),14(18),15-octaene ?
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C21H21N3
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