Cho A =1/1.2 + 1/3.4 + 1/5.6 + ... + 1/99.1001/51.100 + 1/52.99 + ... + 1/100.511/2.1 + 1/3.4 + ... + 1/199.2001/101 + 1/1.2 + ... + 1/2005/2.1 + 4/ 1.11 + 5/11.2 + 1/2.15 + 13/15.4A=?
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