E = (nx 2 + ny 2 + nz 2 ) h2
/(8ma2 ).
Rearranging gives E (8ma2 )/ h2 = (nx
2 + ny 2 + nz 2 )
nx, ny, nz,      Â
   1,1, 1       2,1, 1
       1,2, 1
      1,1, 2
      1,2, 2
      2,1, 2
     2,2, 1
      1,1, 3    1,3, 1
   3,1, 1
E(8ma2 )/ h2
        3       Â
      6
                6
              6     Â
       9
              9
            9
             11
         11
       11
nx, ny, nz,
          2,2, 2
     2,1, 3
     1,2, 3
     3,2, 1    2,3,
1Â Â Â 1,3, 2 Â Â Â Â Â 3,1, 2
     2,2, 3
     2,3, 2     3,2, 2
E(8ma2 )/ h2
         12
           14         Â
14 Â Â Â Â Â Â Â Â 14
          14
         14
          14
            17
           17
         17
   Â
nx, ny, nz,
          1,1, 4
        4,1, 1
          1,4,
1Â Â Â Â Â Â Â 1,3, 3
        3,1, 3
             3,3,
1
E(8ma2 )/ h2
          18
          18
                18
             19
               19
                  19
TOTAL: 17 states and 6 energy levels lie within this range