http://projecteuler.net/problem=28

**Number spiral diagonals**

Starting with the number 1 and moving to the right in a clockwise direction a 5 by 5 spiral is formed as follows:

~~22 23 24~~2125

20~~8~~7~~10~~9

19 6~~2 11~~1

18~~4~~5~~12~~3

~~16 15 14~~1713

It can be verified that the sum of the numbers on the diagonals is 101.

What is the sum of the numbers on the diagonals in a 1001 by 1001 spiral formed in the same way?