12:\(A=\dfrac{11\cdot\left(11+1\right)\cdot\left(2\cdot11+1\right)}{6}=506\)
13: \(S=\dfrac{50\left(50+1\right)\left(2\cdot50+1\right)}{6}=42925\)
14: \(Q=\dfrac{\left(51+1\right)\cdot51\cdot\left(2\cdot51+1\right)}{6}=45526\)
15: \(=\dfrac{100\cdot\left(100+1\right)\left(2\cdot100+1\right)}{6}=338350\)
16: \(=\dfrac{101\left(101+1\right)\left(2\cdot101+1\right)}{6}=348551\)
24: \(=4\left(1^2+2^2+3^2+...+15^2\right)\)
\(=4\cdot\dfrac{15\left(15+1\right)\left(2\cdot15+1\right)}{6}=4960\)
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