For the code snippet given below. Calculate $($using summation$),$ the total number of times

the inner most statement in the for loop is executed.

What kind of summation is this? Expand the summation to find the Big O of the code

snippet to the tightest upper bound.

for $($int i $=0$; i $<$ n; i$++)\{$

for $($int j $=0$; j $<$ pow$(3,$ i$)$; j$++)\{$

total$\_$iterations$++$;

$\}$

$\}$