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**riptorn70** I am told the first $\displaystyle n$ term of a sequence is $\displaystyle n^{2}$, and told to find the $\displaystyle 10^{th}$ term in the sequence, and the smallest value of $\displaystyle r$ for which the $\displaystyle r^{th}$ term exceeds 10 000. By using the left side of the formula

$\displaystyle

sum_{r=1}^n r^2 = \frac{1}{6} n (n+1)(2n+1)$ I think I can find the tenth term but I am unsure how to find the smallest value of $\displaystyle r$ for which the $\displaystyle r^{th}$ term exceeds 10 000.

any hints or guidance would be well met. Thankyou.