摘要

In this paper we discuss the composite functional equation %26lt;br%26gt;f(x + 2f(y)) = f(x) + y + f(y) %26lt;br%26gt;on an Abelian group. This equation originates from Problem 10854 of the American Mathematical Monthly. We give an algebraic description of the solutions on uniquely 3-divisible Abelian groups, and then we construct all solutions f of this equation on finite Abelian groups without elements of order 3 and on divisible Abelian groups without elements of order 3 including the additive group of real numbers.

  • 出版日期2013-9