L_11=1; P(A included)=7/15; P(empty)=4/15; P(A,B)=1/5
E[size] at L=25/17; at 3L=183/103
Fixed k=2 at L and 3L: P(A,B)=4/9, P(A,C)=4/9, P(B,C)=1/9
PASS: 20958 checks; 729 vector matrices; 16 rejected inputs
