49 out of the 50 states are represented in NCAA Division I Men's Basketball (Alaska is not). Of those 49 states, 18 were not represented in the 2012 NCAA Division I Men's Basketball Tournament. They are listed below.
In 2013, assuming that's what you mean by "this year," the NCAA Men's basketball tournament included teams from 31 states and the District of Columbia.
The first NCAA Basketball Tournament was held in 1939.
64 teams in the NCAA tournament in 2000
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The 2012 NCAA men's basketball tournament included teams from 31 states and the District of Columbia.
Alaska
Michigan State did not make the NCAA tournament in 1980 after winning the championship in 1979. Florida did not make the NCAA tournament in 2008 after winning the 2007 championship. North Carolina won the NCAA tournament in 2009 and will not make the tournament in 2010.
The Wisonsin Badgers played in the 2010 NCAA Men's Basketball Tournament.
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