If the value of the integral above is equal to , where and are positive integers with coprime, find .
Notation : denotes the Riemann zeta function .
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Recalling the alternating Euler sum a h ( 1 , 2 ) = n = 1 ∑ ∞ ( n + 1 ) 2 ( − 1 ) n − 1 H n = 8 1 ζ ( 3 ) we observe that n = 1 ∑ ∞ n 2 ( − 1 ) n H n = = = − 1 + n = 1 ∑ ∞ ( n + 1 ) 2 ( − 1 ) n − 1 H n + 1 − 1 + n = 1 ∑ ∞ ( n + 1 ) 2 ( − 1 ) n − 1 H n + n = 1 ∑ ∞ ( n + 1 ) 3 ( − 1 ) n − 1 = a h ( 1 , 2 ) + n = 1 ∑ ∞ n 3 ( − 1 ) n 8 1 ζ ( 3 ) − 4 3 ζ ( 3 ) = − 8 5 ζ ( 3 ) Since ∫ 0 1 x n − 1 ln ( 1 − x ) d x = − m = 1 ∑ ∞ m 1 ∫ 0 1 x n + m − 1 d x = − m = 1 ∑ ∞ m ( m + n ) 1 = − n 1 H n for any n ≥ 1 , we see that ∫ 0 1 x ln ( 1 + x ) ln ( 1 − x ) d x = = n = 1 ∑ ∞ n ( − 1 ) n − 1 ∫ 0 1 x n − 1 ln ( 1 − x ) d x = n = 1 ∑ ∞ n 2 ( − 1 ) n H n = − 8 5 ζ ( 3 ) making the answer 5 + 8 + 3 = 1 6 .