[ Eq(Derivative(x2, t), ((-1)*k13*(k14*x1*x2 - k15*x11) + 1*k13*k10*k26 + (-1)*k13*k10*x2)/k13),
  Eq(Derivative(x3, t), ((-1)*k13*(k16*x3*x5 - k17*x4) + 1*k13*k18*x4 + (-1)*k13*k19*x3 + 1*k13*k25*x11)/k13),
  Eq(Derivative(x4, t), (1*k13*(k16*x3*x5 - k17*x4) + (-1)*k13*k18*x4)/k13),
  Eq(Derivative(x5, t), ((-1)*k13*(k16*x3*x5 - k17*x4) + 1*k13*k23*x6)/k13),
  Eq(Derivative(x6, t), (1*k13*k18*x4 + (-1)*k13*(k20*x6*x7 - k21*x8) + 1*k13*k22*x8 + (-1)*k13*k23*x6)/k13),
  Eq(Derivative(x7, t), ((-1)*k13*(k20*x6*x7 - k21*x8) + 1*k13*k24*x9)/k13),
  Eq(Derivative(x8, t), (1*k13*(k20*x6*x7 - k21*x8) + (-1)*k13*k22*x8)/k13),
  Eq(Derivative(x9, t), (1*k13*k22*x8 + (-1)*k13*k24*x9)/k13),
  Eq(Derivative(x10, t), 0),
  Eq(Derivative(x11, t), (1*k13*(k14*x1*x2 - k15*x11) + (-1)*k13*k25*x11)/k13) ]