param cav_index_start{i in {1..36}};
param cav_index_end{i in {1..36}};
set A1 := {cav_index_start[1]..cav_index_end[1]};
set A11 := {cav_index_start[2]..cav_index_end[2]};
set A111 := {cav_index_start[3]..cav_index_end[3]};
set A2 := {cav_index_start[4]..cav_index_end[4]};
set A22 := {cav_index_start[5]..cav_index_end[5]};
set A222 := {cav_index_start[6]..cav_index_end[6]};
set A3 := {cav_index_start[7]..cav_index_end[7]};
set A33 := {cav_index_start[8]..cav_index_end[8]};
set A333 := {cav_index_start[9]..cav_index_end[9]};
set B1 := {cav_index_start[10]..cav_index_end[10]};
set B11 := {cav_index_start[11]..cav_index_end[11]};
set B111 := {cav_index_start[12]..cav_index_end[12]};
set B2 := {cav_index_start[13]..cav_index_end[13]};
set B22 := {cav_index_start[14]..cav_index_end[14]};
set B222 := {cav_index_start[15]..cav_index_end[15]};
set B3 := {cav_index_start[16]..cav_index_end[16]};
set B33 := {cav_index_start[17]..cav_index_end[17]};
set B333 := {cav_index_start[18]..cav_index_end[18]};
set C1 := {cav_index_start[19]..cav_index_end[19]};
set C11 := {cav_index_start[20]..cav_index_end[20]};
set C111 := {cav_index_start[21]..cav_index_end[21]};
set C2 := {cav_index_start[22]..cav_index_end[22]};
set C22:= {cav_index_start[23]..cav_index_end[23]};
set C222 := {cav_index_start[24]..cav_index_end[24]};
set C3 := {cav_index_start[25]..cav_index_end[25]};
set C33 := {cav_index_start[26]..cav_index_end[26]};
set C333 := {cav_index_start[27]..cav_index_end[27]};
set D11 := {cav_index_start[28]..cav_index_end[28]};
set D11 := {cav_index_start[29]..cav_index_end[29]};
set D111 := {cav_index_start[30]..cav_index_end[30]};
set D2 := {cav_index_start[31]..cav_index_end[31]};
set D22 := {cav_index_start[32]..cav_index_end[32]};
set D222 := {cav_index_start[33]..cav_index_end[33]};
set D3 := {cav_index_start[34]..cav_index_end[34]};
set D33 := {cav_index_start[35]..cav_index_end[35]};
set D333 := {cav_index_start[36]..cav_index_end[36]};
set large_cav = A11 union A22 union A33 union B11 union B22 union B33 union C11 union C22 union C33 union D11 union D22 union D33;
set Middle_cav = A1 union A2 union A3 union B1 union B2 union B3 union C1 union C2 union C3 union D1 union D2 union D3;
set Small_cav = A111 union A222 union A333 union B111 union B222 union B333 union C111 union C222 union C333 union D111 union D222 union D333;

For the sets large_cav, Small_cav, am I writing this correctly?