If $\cot ^ { - 1 } ( \alpha ) = \cot ^ { - 1 } 2 + \cot ^ { - 1 } 8 + \cot ^ { - 1 } 18 + \cot ^ { - 1 } 32 + \ldots$ upto 100 terms, then $\alpha$ is:\\ (1) 1.01\\ (2) 1.00\\ (3) 1.02\\ (4) 1.03