{ x15 = (x3*k22 + x4*k23 + x5*k24 + x6*k22 + x7*k23 + x8*k24)/k20,
  x16 = (x9*k22 + x10*k23 + x11*k24 + x12*k22 + x13*k23 + x14*k24)/k20,
  x17 = (x3*k22 + x4*k23 + x5*k24 + x9*k22 + x10*k23 + x11*k24)/k20,
  x18 = (x6*k22 + x7*k23 + x8*k24 + x12*k22 + x13*k23 + x14*k24)/k20,
  x19 = (x3*k22 + x6*k22 + x9*k22 + x12*k22)/k20,
  x20 = (x4*k23 + x7*k23 + x10*k23 + x13*k23)/k20,
  x21 = (x5*k24 + x8*k24 + x11*k24 + x14*k24)/k20,
  x22 = (x19*k20 + x20*k20 + x21*k20)/k20,
  x43 = x22/k19 }