-- -*- M2-comint -*- {* hash: -991898112 *}

i1 : S = QQ[a,b,c,d];

i2 : M = monomialIdeal (b^2, b*c, c^2);

o2 : MonomialIdeal of S

i3 : L = lcmLattice (M);

i4 : L.GroundSet

       2        2   2    2 2     2
o4 = {b , b*c, c , b c, b c , b*c }

o4 : List

i5 : L.RelationMatrix

o5 = | 1 0 0 1 1 0 |
     | 0 1 0 1 1 1 |
     | 0 0 1 0 1 1 |
     | 0 0 0 1 1 0 |
     | 0 0 0 0 1 0 |
     | 0 0 0 0 1 1 |

              6        6
o5 : Matrix ZZ  <--- ZZ

i6 :