document.write( "Question 982792: 1, 3, 15, 51, 131, ?
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Algebra.Com's Answer #603601 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "First I found the differences\r\n" );
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document.write( "2,12,36,80\r\n" );
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document.write( "I subtracted the squares 1,4,9,16 from those differences\r\n" );
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document.write( "1,8,27,64\r\n" );
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document.write( "I recognized those as the cubes.\r\n" );
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document.write( "So to get the next term, we add the square and the cube of the\r\n" );
document.write( "number of the term\r\n" );
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document.write( "The recursion formula is\r\n" );
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document.write( "an+1 = an + n2 + n3, a1 = 1 \r\n" );
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document.write( "Start with 1\r\n" );
document.write( "Add 12+13, which is 1+1=2, get 3\r\n" );
document.write( "Add 22+23, which is 4+8=12, get 15\r\n" );
document.write( "Add 32+33, which is 9+27=36, get 51\r\n" );
document.write( "Add 42+43, which is 16+64=80, get 131\r\n" );
document.write( "Add 52+53, which is 25+125=150, get 281\r\n" );
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document.write( "Edwin
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