<s>[INST] How do we find the $n+2$th term of the series $1 + (3+5) + (7+9+11)+\dots$? We have the series $1 + (3+5) + (7+9+11)+\dots$. 
We need to find the  $n+2$th  term and hence summation of the series up to this term.
However hard we try we do not seem to be able to fit this series to a pattern.
 [/INST] $$a_{1}=1=1^3\\a_{2}=3+5=8=2^3\\a_{3}=7+9+11=27=3^3\\a_{4}=13+15+17+19=64=4^3\\...\\a_{n}=n^3\\so\\a_{n+2}=(n+2)^3$$
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