  Given pairwise distinct vertices $\{\alpha_i , \beta_i\}^k_{i=1}$ of the
$n$-dimensional hypercube $Q_n$ such that the distance of $\alpha_i$ and
$\beta_i$ is odd, are there paths $P_i$ between $\alpha_i$ and $\beta_i$ such
that $\{V (P_i)\}^k_{i=1}$ partitions $V(Q_n)$? A positive solution for every
$n\ge1$ and $k=1$ is known as a Gray code of dimension $n$. In this paper we
settle this problem for small values of $n$.
