Number of n X n binary matrices with zero diagonal and no 2-loops or directed 3-loops (3-loop: x(i,j)*x(j,k)*x(k,i)=1, and i,j,k all different).

A213599

Number of n X n binary matrices with zero diagonal and no 2-loops or directed 3-loops (3-loop: x(i,j)*x(j,k)*x(k,i)=1, and i,j,k all different).

Terms

    a(0) =1a(1) =3a(2) =25a(3) =549a(4) =30535a(5) =4168935a(6) =1362083785

External references