MathCastle
ChallengeSuperchallenge

Challenge · Superchallenge problem

Compute ∑k≡1(mod4)(24k)\displaystyle\sum_{k \equiv 1 \pmod{4}} \binom{24}{k}, the sum of (24k)\binom{24}{k} over all kk from 00 to 2424 with k≡1(mod4)k \equiv 1 \pmod{4}.

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