Has there been any suggestions for a symbol for "cover" relation on posets? (For example on the poset $(\mathbb{Z}, \mid)$ number 12 covers number 6, but does not cover number 3.)
Texts I have seen just says "$a$ covers $b$" or explicitly states "$a \succ b$ and there is no $c$ such that $a \succ c$ and $c \succ b$".
I happen to found an example. Enumerative Combinatorics, downloadable from http://math.mit.edu/~rstan/ec/ec1/ , on p. 279 uses \lessdot for this.