A=\(\dfrac{1}{2}\)+\(\dfrac{1}{6}+\dfrac{1}{12}+\dfrac{1}{20}+\dfrac{1}{30}+-+\dfrac{1}{9900}\)

B=\(\dfrac{1}{1.3}+\dfrac{1}{3.5}+\dfrac{1}{5.7}+-+\dfrac{1}{2009.2011}\)

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