Minimum Sum of Array using Tabular Recipe

def minSumArr():
    arr = [2,2,3,5,6] or [1,2,2]
    n = len(arr)
    sum, prev = arr[0], arr[0]
    
    for i in range(1,n):
        if arr[i]<=prev:
            prev = prev+1 
            sum = sum+prev
        else:
            sum = sum+arr[i]
            prev = arr[i]
    print(sum)
    
minSumArr()

'''output 20
      or
   output 6
   '''