Solver configuration for a fairly complex sheet.

Hi folks!

I need 2 level ones to get 1 level two. 2 level twos to get 1 level three. 2 level threes to get 1 level four, and so on.
Formula for number of level ones to get 1 of level N is: X = 2^(N-1).
I got this built on a sheet and now I need to find minimum number of level ones to get 1 level N having certain numbers of level K's between level 1 and level N.

I tried Goal Seek and it finds a solution but it's not minimum. Found out Goal Seek does not have feature to search for minimums.

So I tried Solver. I set up objective and constraints but solution is not found. Instead I get Feasibility errors.

I'm not familiar with Solver and my scenario might be erronous or maybe the sheet is too complex. Could someone please check the setup on workbook attached.

Any help highly appreciated, thanks in advance