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aligned & A₁= [a₁ ] & A₂= [ array ll a₂ & a₃ a₄ & a₅ array ] & A₃= [ array lll a₆ & a₇ & a₈ a₉ & a₁₀ & a₁₁ a₁₂ & a₁₃ & a₁₄ array ] . . A_n=[ . .] aligned Where a _ r = [ ₂ r ] ([.] denotes greatest integer). Then trace of A ₁₀ is equal to

Correct answer

80

Step-by-step solution

First element in A ₁₀ is a _ 1^2+2^2+3^2+ . . .9^2+1 = a ₂₈₆ and [a₂₈₆ ]=8 and last element is a ₃₈₅ aligned & a₃₈₅= [ ₂ 385 ]=8 & Sum =80 aligned

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