[ Eq(Derivative(x1, t), ((-1)*k15*k1*x1*x11*(1 + (x11/k2)**k3)**(-1) + 1*k15*k10)/k15),
  Eq(Derivative(x2, t), ((-1)*k16*k1*x2*x12*(1 + (x12/k2)**k3)**(-1) + 1*k16*k10)/k16),
  Eq(Derivative(x3, t), (2*k15*k1*x1*x11*(1 + (x11/k2)**k3)**(-1) + (-1)*k15*k4*x3*x16 + (-1)*k15*k8*x3*x9)/k15),
  Eq(Derivative(x4, t), (2*k16*k1*x2*x12*(1 + (x12/k2)**k3)**(-1) + (-1)*k16*k4*x4*x17 + (-1)*k16*k8*x4*x10)/k16),
  Eq(Derivative(x5, t), (1*k15*k4*x3*x16 + (-1)*k15*k5*x5*x18)/k15),
  Eq(Derivative(x6, t), (1*k16*k4*x4*x17 + (-1)*k16*k5*x6*x19)/k16),
  Eq(Derivative(x7, t), (1*k15*k5*x5*x18 + (-1)*k15*k6*x7*x9 + (-1)*k15*k13*(x7 - x13))/k15),
  Eq(Derivative(x8, t), (1*k16*k5*x6*x19 + (-1)*k16*k6*x8*x10 + (-1)*k16*k13*(x8 - x13))/k16),
  Eq(Derivative(x9, t), (1*k15*k4*x3*x16 + (-1)*k15*k6*x7*x9 + (-1)*k15*k8*x3*x9)/k15),
  Eq(Derivative(x10, t), (1*k16*k4*x4*x17 + (-1)*k16*k6*x8*x10 + (-1)*k16*k8*x4*x10)/k16),
  Eq(Derivative(x11, t), ((-2)*k15*k1*x1*x11*(1 + (x11/k2)**k3)**(-1) + 2*k15*k5*x5*x18 + (-1)*k15*k7*x11)/k15),
  Eq(Derivative(x12, t), ((-2)*k16*k1*x2*x12*(1 + (x12/k2)**k3)**(-1) + 2*k16*k5*x6*x19 + (-1)*k16*k7*x12)/k16),
  Eq(Derivative(x13, t), ((-1)*k17*k9*x13 + 1*k17*k14/2*(k13*(x7 - x13) + k13*(x8 - x13)))/k17),
  Eq(Derivative(x14, t), 0),
  Eq(Derivative(x15, t), 0) ]