Ternary universal sums of generalized pentagonal numbers

Byeong-Kweon Oh

For any $m\ge 3$, every integer of the form $p_m(x)=\frac{(m-2)x^2-(m-4)x}{2}$ with $x \in \z$ is said to be a generalized $m$-gonal number. Let $a\le b\le c$ be positive integers. Fo…