a(m,k)  tabf head (staircase) for  A091029 


   m\k      0      1      2      3      4      5      6      7      8      9     10

   2        1      0      0      0      0      0      0      0      0      0      0
                      
   3        3     -2      0      0      0      0      0      0      0      0      0
                      
   4        2      6     -9      3      0      0      0      0      0      0      0
                      
   5       15      0    -24     18     -4      0      0      0      0      0      0
                      
   6        5     69    -75    -20     60    -30      5      0      0      0      0
                      
   7       63    217   -462    225     80   -120     45     -6      0      0      0
                      
   8       14    462    300  -1848   1785   -525   -210    210    -63      7      0
                      
   9      252   2460  -1809  -4932   8428  -5208   1050    448   -336     84     -8
                                                                     
 
 The sequence of the lengths of the rows is [1,2,4,5,7,8,10,11,13,14,...]=A001651(m-2)= floor((3*m-4)/2).