def triangles():

L0 = [1,1]
n = 1
while True:
    L = []
    for i in range(n):
        if i == 0 or i == n-1:
            L.append(1)
        else:
            L.append(L0[i]+L0[i-1])

    yield L
    L0 = L
    n = n + 1

n = 0 for t in triangles(): print(t) n = n + 1 if n == 10: break