document.write( "Question 1099427: n>k+s+2 . How many permutations has the set {1,2,3...n} ,with condition that in the middle of the numbers 1 and 2 ( and 2 and 1) are exactly k numbers and in the middle of the numbers 2 and 3 (and 3 and 2 ) are exactly (k+1) numbers? \n" ); document.write( "
Algebra.Com's Answer #713991 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "What does \"the middle of the numbers 1 and 2\" and \r\n" );
document.write( "\"the middle of the numbers 2 and 3\" mean?  I've only heard\r\n" );
document.write( "\"middle of numbers\" referring to their arithmetic average or mean.\r\n" );
document.write( "Surely you don't mean the average of 1 and 2, which is 1.5, and\r\n" );
document.write( "the average of 2 and 3, which is 2.5.  That wouldn't make any sense.\r\n" );
document.write( "Please tell us what you're talking about.  You can use the message \r\n" );
document.write( "form below.\r\n" );
document.write( "Edwin
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