A column of numbers 1, 3.5, 7, 9, 11, 13... So what's the 100th number Why? What's the law? It's 1, - 3. - 7, 11, - 13··· sorry | Math enthusiast | Mathematical art

A column of numbers 1, 3.5, 7, 9, 11, 13... So what's the 100th number Why? What's the law? It's 1, - 3. - 7, 11, - 13··· sorry

-199 (the rule is 2n + 1, and the odd number is positive, and the even number is negative)

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