On the Erdos-Sos Conjecture for Graphs on n=k+4 Vertices
  The Erd\H{o}s-S\'{o}s Conjecture states that if $G$ is a simple graph of order $n$ with average degree more than $k-2,$ then $G$ contains every tree of order $k$. In this paper, we prove that Erd\H{o}s-S\'{o}s Conjecture is true for $n=k+4$. 
Long-Tu Yuan and Xiao-Dong Zhang
math.CO