1^4 = 1
2^4 = 16
3^4 = 81
4^4 = 256
5^4 = 625
6^4 = 1296
7^4 = 2401
So there are 15 terms equal to 1/1, (81-16) terms equal to 1/2, etc.
Final answer =
(16-1)/1 + (81-16)/2 + (256-81)/3 + (625-256)/4 + (1296 - 625)/5 + (2015 - 1296)/6 = 27127/60, which is approx 452.11667