My code is returning 10, which ... seems to be correct by my count ... fed birds would be represented by the helpings [spoiler]6+5+5+4+4+4+3+3+3+3 = 40 portions. Am I misunderstanding something in the requirements?

      t | birds | max_portions |               max_helpings                 |     max_per_flock        
     ---|-------|--------------|--------------------------------------------|-----------------------
      5 |  15   |     35       | 5,4,4,3,3,3,2,2,2,2,1,1,1,1,1              | 5[8][9][8][5]
      6 |  21   |     56       | 6,5,5,4,4,4,3,3,3,3,2,2,2,2,2,1,1,1,1,1,1  | 6[10][12][12][10][6]