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What is the molecular formula of the compound with this IUPAC name chromium(3+);methanone;2,8,14-trithia-19,20,21-triazatetracyclo[13.3.1.13,7.19,13]henicosa-1(19),3(21),4,6,9(20),10,12,15,17-nonaene ?
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C18H12CrN3O3S3
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