document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1209383>Question 1209383</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Prove that n^2-n is always even </SPAN>\n" );
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document.write( "The statement of the problem is deficient; n^2-n is NOT always even.  It is always even IF n IS AN INTEGER.<br><BR>\n" );
document.write( "n^2-n = n(n-1)<br><BR>\n" );
document.write( "If n is an integer, then that expression is the product of two consecutive integers.  In any two consecutive integers, one of them is odd and the other is even; and the product of two integers is even whenever at least one of them is even.<br><BR>\n" );
document.write( "So the product of two consecutive integers is always even.<br><BR>\n" );
document.write( "TRUE: n^2-n is always even if n is an integer<br><BR>\n" );
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