[ Eq(Derivative(x1, t), (1*k17*k1*x3 + 1*k17*k7*x1*x3*(1 - (x1 + x2)/k5) + (-1)*k17*k13*x1)/k17),
  Eq(Derivative(x2, t), (1*k17*k2*x4 + 1*k17*k8*x2*x4*(1 - (x2 + x1)/k5) + (-1)*k17*k14*x2)/k17),
  Eq(Derivative(x3, t), (1*k17*k3*x1 + 1*k17*k9*x3*(1 - (x3 + x4)/k6) + (-1)*k17*k15*x3 + (-1)*k17*k12*x3 + 1*k17*k11*x4)/k17),
  Eq(Derivative(x4, t), (1*k17*k12*x3 + (-1)*k17*k11*x4 + 1*k17*k4*x2 + 1*k17*k10*x4*x2*(1 - (x4 + x3)/k6) + (-1)*k17*k16*x4)/k17) ]