[iironiic]

Originally Posted by emerald000

Let's take f(95). Its 100 digits are: (note my program counts backwards)

7, 2, 5, 5, 6, 0, 8, 3, 0, 6, 9, 0, 2, 1, 7, 8, 4, 8, 6, 5, 3, 9, 4, 2, 0, 6, 4, 2, 7, 7, 1, 8, 0, 0, 2, 7, 5, 0, 0, 0, 5, 7, 1, 9, 9, 1, 3, 0, 1, 9, 4, 7, 3, 3, 0, 0, 9, 3, 8, 5, 2, 5, 2, 9, 9, 2, 0, 0, 6, 9, 9, 8, 9, 9, 1, 3, 1, 4, 8, 3, 8, 6, 0, 9, 3, 6, 9, 8, 0, 8, 4, 4, 3, 4, 9, 7, 6, 4, 7, 9

which gives a sum of 459. The 101st decimal is a 6, so if rounded up the 7, you would get to your answer of 460.

And yes the problem isn't clear, but thanks to the example, you can understand they mean to have 100 significant digits.

Thanks! I just got 80 and 69 now! :)