A086131 Largest prime factor of arithmetic derivative of n if it exists, or a(n)=0 for n=1 and n=prime.

0, 0, 0, 2, 0, 5, 0, 3, 3, 7, 0, 2, 0, 3, 2, 2, 0, 7, 0, 3, 5, 13, 0, 11, 5, 5, 3, 2, 0, 31, 0, 5, 7, 19, 3, 5, 0, 7, 2, 17, 0, 41, 0, 3, 13, 5, 0, 7, 7, 5, 5, 7, 0, 3, 2, 23, 11, 31, 0, 23, 0, 11, 17, 3, 3, 61, 0, 3, 13, 59, 0, 13, 0, 13, 11, 5, 3, 71, 0, 11, 3, 43, 0, 31, 11, 5, 2, 7, 0, 41, 5, 3