Question 333459
at layer k there are 3^k parents, where k=1 to 5
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total = {{{sum (3^k)}}} k=1 to 5
total ={{{(3^(5+1)-3)/(3-1)=(3^6-3)/2=363}}}
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note: 
In general
total = {{{sum (r^k)}}} k=1 to n 
total ={{{(r^(n+1)-r)/(r-1)}}}