a(n,m)  tabf head (staircase) for  A090452 (scaled A078740: (32)-Stirling2)

   
   n\m   2    3    4     5      6      7       8       9      10     11     12      13     14     15    16
 
    1    1    0    0     0      0      0       0       0       0      0      0       0      0      0     0
                       
    2    1    3    2     0      0      0       0       0       0      0      0       0      0      0     0
                        
    3    1    7   16    15      5      0       0       0       0      0      0       0      0      0     0
                       
    4    1   12   51   105    114     63      14       0       0      0      0       0      0      0     0
                       
    5    1   18  118   396    771    910     644     252      42      0      0       0      0      0     0
                       
    6    1   25  230  1110   3235   6083    7580    6240    3270    990    132       0      0      0     0
                        
    7    1   33  402  2600  10365  27483   50464   65331   59625  37620  15642    3861    429      0     0
                    
    8    1   42  651  5390  27825  97188  240751  434493  578690 569415 409332  209209  72072  15015  1430


  The sequence of row lengths is [1,3,5,7,...]=A005408(n-1).