document.write( "Question 545656: What is the differance in this sequence? 7,14,23,34,47,62,79,98,119,142,167,194! What is the nth number? \n" ); document.write( "
Algebra.Com's Answer #355668 by Edwin McCravy(20056)\"\" \"About 
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document.write( "7,14,23,34,47,62,79,98,119,142,167,194,...\r\n" );
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document.write( "We notice that if we add 2 to each of those we get this \r\n" );
document.write( "familiar sequence of squares:\r\n" );
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document.write( "9,16,25,36,49,64,81,100,121,144,169,196,...\r\n" );
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document.write( "which equals\r\n" );
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document.write( "3²,4²,5²,6²,7²,8²,9²,10²,11²,12²,13²,14²,...\r\n" );
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document.write( "Connecting it with the sequence 1,2,3,...\r\n" );
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document.write( "(1+2)²,(2+2)²,(3+2)²,(4+2)²,(5+2)²,(6+2)²,(7+2)²,(8+2)²,(9+2)²,(10+2)²,(11+2)²,(12+2)², \r\n" );
document.write( "which has nth term (n+2)².\r\n" );
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document.write( "The original sequence has terms which are 2 less than the terms of this\r\n" );
document.write( "sequence, so the nth term of the original sequence is (n+2)²-2 = n²+4n+4-2 or\r\n" );
document.write( "n²+4n+2\r\n" );
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document.write( "So the nth number is n²+4n+2.\r\n" );
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document.write( "Edwin
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