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APMO 1997 - Asian Pacific Mathematics Olympiad Question 1

APMO · APMO 1997 - Asian Pacific Mathematics Olympiad

Question 1

Given
$$S=1+\frac1{1+\frac13}+\frac1{1+\frac13+\frac16}+\cdots+\frac1{1+\frac13+\frac16+\cdots+\frac1{1993006}},$$
where the denominators are partial sums of the reciprocals of triangular numbers $k=n(n+1)/2$ for $n=1,2,\ldots,1996$, prove that $S\gt 1001$.