{ 1*k13*x2 + 1*k13*x7 + 1*k13*x8 + 1*k13*x9 + 1*k13*x10 = k13*k14,
  1*k13*x3 + 1*k13*x8 + 1*k13*x9 + 1*k13*x10 + 1*k13*x11 + 1*k13*x12 = k13*k15,
  1*k13*x4 + 1*k13*x13 = k13*k16,
  1*k13*x5 + 1*k13*x14 = k13*k17,
  1*k13*x5 + 1*k13*x15 = k13*k18,
  1*k13*x6 + 1*k13*x16 = k13*k19,
  1*k13*x6 + 1*k13*x17 = k13*k20 }