The sum of n terms of \[1+\frac{1+2}{2}+\frac{1+2+3}{3}+...\]is

1.	The sum of n terms of \[1+\frac{1+2}{2}+\frac{1+2+3}{3}+...\]is
A.	\[\frac{m(n+3)}{4}\]
B.	\[\frac{(n+3)}{3}\]
C.	\[\frac{n(n-3)}{3}\]
D.	\[\frac{n(n-3)}{4}\]
Answer» B. \[\frac{(n+3)}{3}\]

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The sum of n terms of \[1+\frac{1+2}{2}+\frac{1+2+3}{3}+...\]is

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