Project Euler Problem #28

p28.py

spiral_side = 1001
num_corners = spiral_side/2

total = 1
corners = (1, 1, 1, 1)
additions = (2, 4, 6, 8)

for i in xrange(num_corners):
  corners = map(sum, zip(corners, additions))
  additions = map(lambda x: x+8, additions)
  total += sum(corners)

print total