1的立方加3的立方,一直加到99的立方

T=1^3+3^3+5^3+...+(2n-1)^3=Σ(8n^3-12n^2+6n-1)=2[n(n+1)]^2-2n(n+1)(2n+1)+3n(n+1)-n=n^2(2n^2-1)当n=50时,T(50)=2500*(5000-1)=12497500.