# Problem 421: Prime factors of n15+1
Numbers of the form n15+1 are composite for every integer n > 1. For
positive integers n and m let s(n,m) be defined as the sum of the
distinct prime factors of n15+1 not exceeding m. E.g. 215+1 =
3×3×11×331. So s(2,10) = 3 and s(2,1000) = 3+11+331 = 345. Also 1015+1 =
7×11×13×211×241×2161×9091. So s(10,100) = 31 and s(10,1000) = 483. Find
∑ s(n,108) for 1 ≤ n ≤ 1011.