Q[a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,u]
{
o*s+n*u,m*s+l*u,b*s-a*u,j*r+i*s,f*r+e*s,c*r-a*u,o*q+m*r,n*q+l*r,j*q+f*u,i*q+e*u,d*q-a*u,m*n-l*o,b*n+a*o,d*m+c*o,i*l-f*o,d*l+c*n,b*l+a*m,f*i-e*j,c*i+b*j,d*f+a*j,d*e+a*i,c*e+b*f
}