Same entry and exit node?

[mw_prev1 at fastmail.fm]

I notice that everytime I run Tor it opens connections to several nodes.
 I know this is normal, but recently I ran Tor and checked my IP - it
showed that my IP (i.e. the exit node) was the SAME IP as one of the
entry nodes I was connected to!

I cleared the browser cache beforehand so it can't be a cache problem.

Surely this can't be right, is it really possible that Tor can use the
same node for entry and exit?
-- 
  
  mw_prev1 at fastmail.fm

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