(Rockaway Beach, OR)  --  The Coast Guard is calling off the search for a Colorado teen missing off the Oregon coast.  Coast Guard officials announced yesterday that 17-year-old Samuel Allen remains missing and is presumed dead.  Police say the teen was boogie boarding at Rockaway Beach Wednesday when a wave knocked him off his board, prompting his 50-year-old father Robert Allen to run into the water to try to rescue him.  A Coast Guard crew later recovered the father's body from the surf.