  The sign coherence phenomenon is an important feature of c-vectors in cluster
algebras with principal coefficients. In this note, we consider a more general
version of c-vectors defined for arbitrary cluster algebras of geometric type
and formulate a conjecture describing their asymptotic behavior. This
conjecture, which is called the asymptotic sign coherence conjecture, states
that for any infinite sequence of matrix mutations that satisfies certain
natural conditions, the corresponding c-vectors eventually become sign
coherent. We prove this conjecture for rank 2 cluster algebras of infinite type
and for a particular sequence of mutations in a cluster algebra associated with
the Markov quiver.
