Pascal's triangle

pascals_triangle.py

import copy


init_array = [1, 0, 0, 0, 0, 0, 0, 0, 0]

for i in range(1, 10):
    copy_array = copy.copy(init_array)

    if i != 1:
        copy_array.insert(0, 1)
        copy_array.pop(9)
        for j in range(9):
            init_array[j] = init_array[j] + copy_array[j]

    buf = []
    for k in range(i):
        buf.append(str(copy_array[k]))

    print(' '.join(buf))

$ python pascals_triangle.py
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
1 5 10 10 5 1
1 6 15 20 15 6 1      
1 7 21 35 35 21 7 1   
1 8 28 56 70 56 28 8 1