{ diff(x1, t) = (1*k1*k2*k63/(k3*(1 + x1/k4) + k63) + (-1)*k1*k14*x1/k15*k61/k16/((1 + k61/k16)*(1 + x2/k17 + x1/k15 + 113/1000*x3/k18 + 23/400*x3/k19)) + (-1)*k1*k20/(1 + x1/k21)*x1/k22*k61/k23/(1 + x1/k22 + k61/k23 + x1*k61/(k22*k23) + k60/k24) + (-1)*k1*(-k38)*(x5*k59 - x1*8231/10000*x3/k39)/(x5*k59*(1 + x1/k40) + k41*(k59 + k42) + k43*x5 + k38/(k44*k39)*(k45*x1*(1 + k59/k42) + 8231/10000*x3*(k46*(1 + k43*x5/(k42*k41)) + x1*(1 + x5/k47)))) + 1*k1*k48/(1 + x2/k49)*x5/(k50*(1 + x1/k51) + x5))/k1,
  diff(x2, t) = (1*k1*k5*k62/(k6*(1 + x2/k7) + k62) + (-1)*k1*k8*x2/k9*k61/k10/((1 + k61/k10)*(1 + x2/k9 + x1/k11 + 113/1000*x3/k12 + 23/400*x3/k13)) + 1*k1*k48/(1 + x2/k49)*x5/(k50*(1 + x1/k51) + x5))/k1,
  diff(x3, t) = (1*k1*k8*x2/k9*k61/k10/((1 + k61/k10)*(1 + x2/k9 + x1/k11 + 113/1000*x3/k12 + 23/400*x3/k13)) + 1*k1*k14*x1/k15*k61/k16/((1 + k61/k16)*(1 + x2/k17 + x1/k15 + 113/1000*x3/k18 + 23/400*x3/k19)) + 1*k1*k20/(1 + x1/k21)*x1/k22*k61/k23/(1 + x1/k22 + k61/k23 + x1*k61/(k22*k23) + k60/k24) + (-2)*k1*k25*(23/400*x3*8231/10000*x3 - x4*k59/k26)/(23/400*x3*8231/10000*x3*(1 + x4/k27) + k28*(1 + k58/k29)*(8231/10000*x3 + k30) + k31*23/400*x3 + k25/(k32*k26)*(k33*x4*(1 + 8231/10000*x3/k30) + k59*(k34*(1 + k31*23/400*x3/(k30*k28*(1 + k58/k29))) + x4*(1 + 23/400*x3/k35)))) + (-1)*k1*(-k38)*(x5*k59 - x1*8231/10000*x3/k39)/(x5*k59*(1 + x1/k40) + k41*(k59 + k42) + k43*x5 + k38/(k44*k39)*(k45*x1*(1 + k59/k42) + 8231/10000*x3*(k46*(1 + k43*x5/(k42*k41)) + x1*(1 + x5/k47)))) + (-1)*k1*k52*23/400*x3/(k53 + 23/400*x3))/k1,
  diff(x4, t) = (1*k1*k25*(23/400*x3*8231/10000*x3 - x4*k59/k26)/(23/400*x3*8231/10000*x3*(1 + x4/k27) + k28*(1 + k58/k29)*(8231/10000*x3 + k30) + k31*23/400*x3 + k25/(k32*k26)*(k33*x4*(1 + 8231/10000*x3/k30) + k59*(k34*(1 + k31*23/400*x3/(k30*k28*(1 + k58/k29))) + x4*(1 + 23/400*x3/k35)))) + (-1)*k1*k36*x4/(k37 + x4))/k1,
  diff(x5, t) = (1*k1*k36*x4/(k37 + x4) + 1*k1*(-k38)*(x5*k59 - x1*8231/10000*x3/k39)/(x5*k59*(1 + x1/k40) + k41*(k59 + k42) + k43*x5 + k38/(k44*k39)*(k45*x1*(1 + k59/k42) + 8231/10000*x3*(k46*(1 + k43*x5/(k42*k41)) + x1*(1 + x5/k47)))) + (-1)*k1*k48/(1 + x2/k49)*x5/(k50*(1 + x1/k51) + x5) + (-1)*k1*k54*x5/(k55 + x5))/k1,
  diff(x6, t) = 0,
  diff(x7, t) = 0,
  diff(x8, t) = 0,
  diff(x9, t) = 0,
  diff(x10, t) = 0,
  diff(x11, t) = 0,
  diff(x12, t) = 0,
  diff(x13, t) = 0 }