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Counting & ProbabilityEasyBinomial Theorem, Pascal & Combinatorial Identities

Binomial Theorem, Pascal & Combinatorial Identities · Easy problem

Write 1+2+3+⋯+101+2+3+\cdots+10 as a sum ∑i=110(i1)\sum_{i=1}^{10}\binom{i}{1} and use Hockey Stick to evaluate it.