Sum of products of binomial coefficients

\[\large\sum_{i+j+k+l=2016} \binom{505}{i}\binom{505}{j}\binom{505}{k}\binom{505}{l}\] Find the previous sum over all possible quadruples of non-negative integers \(i,\:j,\:k,\) and \(l,\) where each one of these indexes is less than or equal to 505, and their sum is 2016 as indicated above.

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