12.5.17 Olympic Algebra

Condition: let \ (f (x) = 1+a_ {1} x+a_ {2} x^{2}+\ cdots \) and let all the coefficients in the decomposition of the relationship \ (F^\ Prime} (x) / f (x) \) by degrees \ (x \) do not exceed 2. DOWN \ left | a_ {n} \ right |.