4 problems

Let $f$ be a non-constant entire function, let $k$ be an integer, and let $a_1$ and $a_2$ be two distinct small functions of $f$. Li and Yang's conjecture. If $f$ and $f^{(k)}$ sha…

Let $f$ and $g$ be two distinct non-constant meromorphic functions of infinite order, and let $a_1,a_2,a_3,a_4$ be four distinct values in the extended complex plane. Nonexistence…

Let $f$ and $g$ be two distinct transcendental meromorphic functions of infinite order, and let $a_1,a_2,a_3,a_4$ be four distinct values in the extended complex plane. Four-value…

Let $f$ be a transcendental entire function and let $n$ be a positive integer. Let $k$ be a positive integer, and let $Q_{1}$ and $Q_{2}$ be polynomials with…