  Following Bhargava and Hanke's celebrated 290-theorem, we prove a
universality theorem for all positive-definite integer-valued quadratic forms
that represent all positive integers coprime to $3$. In particular, if a
positive-definite quadratic form represents all positive integers coprime to
$3$ and $\leq 290$, then it represents all positive integers coprime to $3$. We
use similar methods to those used by Rouse to prove (assuming GRH) that a
positive-definite quadratic form representing every odd integer between $1$ and
$451$ represents all positive odd integers.
