find the sum of the following series up to n terms  1^3/1+ (1^3+2^3)/1+3+ (1^3+2^3+3^3)/1+3+5+ ....

Dear student
131+13+231+3+13+23+331+3+5+....Let Tn be the nth term of the given series.Then,Tn=13+23+33+...+n31+3+5+...+2n-1=n(n+1)22n21+2n-1=n24n+12n21+(2n-1)=n2n+122n=n+124=14n2+2n+1Let Sn denote the sum of n terms of the given series.Then,Sn=k=1nTk=k=1n14k2+2k+1=14k=1nk2+2k=1nk+k=1n1=14nn+12n+16+2n(n+1)2+n=124n2n2+n+2n+1+14n2+n+14n=1242n3+3n2+n+6n2+6n+6n=n242n2+9n+13
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