Let $A$ be the sum of the first $20$ terms and $B$ be the sum of the first $40$ terms of the series $1^{2} + 2.2^{2} + 3^{2} + 2.4^{2} + 5^{2} + 2.6^{2} + .....$ If $B - 2A = 100\lambda$, then $\lambda$ is equal to
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