Calculate A*B-C-D
Look at the series (7, 4, 5, 12, 45, D, 1329, 9300, 74397, C, B, A, ...), determine the pattern, and find the unknown values (A, B, C and D) and calculate A*B-C-D!Correct answers: 19
The first user who solved this task is Nílton Corrêa de Sousa.
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