Sequence - Sum

SOURCE:COMPETITION
Number of Problems: 4. : (Book)

 

 

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What is the difference between the sum of the first 2003 even counting numbers and the sum of the first 2003 odd counting numbers?

mathrm{(A) } 0qquad mathrm{(B) } 1qquad mathrm{(C) } 2qquad mathrm{(D) } 2003qquad mathrm{(E) } 4006

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