document.write( "Question 215180This question is from textbook Topics in Finite and Discrete Mathematics
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Algebra.Com's Answer #162590 by Edwin McCravy(20055)\"\" \"About 
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How many permutations are there of 1,2,...,2n have
\n" ); document.write( "every even number in an even-numbered position?
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document.write( "There are \"n\" even integers and \"n\" odd integers.\r
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document.write( "There are \"n%21\" ways to place the even integers.
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document.write( "For every one of those ways, there are \"n%21\" ways 
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document.write( "to place the odd integers.\r
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document.write( "That's  \"n%21%2An%21=n%21%5E2\"\r
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document.write( "Edwin \n" );
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