What is the sum of the series 1 +1 / 2 +1 / 3 +1 / 4 ... up to 1/n ?
What is the sum of the series -LSB- math -RSB- n +2 -LRB- n-1 -RRB- +2 ^ 2 -LRB- n-2 -RRB- + \ ldots +2 ^ -LCB- n-1 -RCB- ? -LSB- / math -RSB-