Calculation: ((1+2)/2)*((1+2+3)/(2+3))*((1+2+3+4)/(2+3+4))*-- -*((1+2+---+2001)/(2+3+---+2001)).
计算：((1+2)/2)*((1+2+3)/(2+3))*((1+2+3+4)/(2+3+4))*---*((1+2+---+2001)/(2+3+---+2001))．
<gadget id="calculator">2_001 / 2_003</gadget>
<output>2_001/2_003 = around 0.999001</output>

<gadget id="calculator">3 * (2_001/2_003)</gadget>
<output>6_003/2_003 = around 2.997004</output>

<result>6_003/2_003 = around 2.997004</result>