1+3+5+7+...+1999+2001.
1+3+5+7+…+1999+2001．
<gadget id="calculator">2_000 * 500</gadget>
<output>1_000_000</output>

<gadget id="calculator">1_000_000 + 2_001</gadget>
<output>1_002_001</output>

<result>1_002_001</result>