第n个等式：(n^2-2n+2)+(n^2-2n+3)+……+(n^-1)+n^2=(n-1)^3+n^3
找规律,
1=0^3+1^3
2+3+4=(2^2-2*2+2)+(2^2-2*2-3)+(2^2-2*2-4)=1^3+2^3