\title{Skein theory for the $D_{2n}$ planar algebras} \author{Scott~Morrison} \address{ Microsoft Station Q, University of California, Santa Barbara 93106-6105 }% \email{scott@tqft.net} \author{Emily~Peters\thanks{Supported in part by NSF Grant DMS0401734} } \address{ Department of Mathematics, University of California, Berkeley, 94720 }% \email{eep@math.berkeley.edu} \author{Noah~Snyder\thanks{Supported in part by RTG grant DMS-0354321} } \address{ Department of Mathematics, University of California, Berkeley, 94720 }% \email{nsnyder@math.berkeley.edu} \urladdr{\url{http://tqft.net/} \url{http://math.berkeley.edu/~eep} \url{http://math.berkeley.edu/~nsnyder}} \date{ First edition: August 6 2008 } \primaryclass{46L37} \secondaryclass{57M15 46M99} \keywords{ Planar Algebras, Subfactors, Skein Theory }