import matplotlib.pyplot as plt

j = [60]
a = [140]

for i in range(1000):
    j_old = j[-1]
    a_old = a[-1]
    j_new = 0.05*j_old + 0.65*a_old - 52
    a_new = 0.45*j_old + 0.68*a_old + 72
    j.append(j_new)
    a.append(a_new)

plt.scatter(range(len(j)),j,label="j")
plt.scatter(range(len(a)),a,label="a")
plt.legend()

j[-1]

a[-1]