CMR:1 x 2 - 1/2! + 2 x 3 - 1/3! + 3 x 4 - 1/4! + ......+ 99 x 100 - 1/100

CMR:1x2-1/2!+2x3-1/3!+3x4-1/4!+......+99x100-1/100!<2
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