document.write( "Question 1193484: The number of trees damaged reported over a four year period 20, 41,83,167 Find the recursive formula
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Algebra.Com's Answer #825521 by ikleyn(52798)\"\" \"About 
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document.write( "The recursive formula is (or can be taken in the form)\r\n" );
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document.write( "    N(k) = 2*N(k-1) + 1,  k = 2, 3, 4\r\n" );
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document.write( "for given values.\r\n" );
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document.write( "Please check it on your own that this formula really works.\r\n" );
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document.write( "When you complete checking and will prove for yourself that the formula works,\r\n" );
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document.write( "you may use it to move further and predict/calculate  N(k)  for k = 5, 6 and 7.\r\n" );
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document.write( "I leave this simple job for you.\r\n" );
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document.write( "You may report me about your progress.\r\n" );
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document.write( "    T      A      B      L      E\r\n" );
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document.write( "  k            Given         Calculated \r\n" );
document.write( "               numbers       using the formula\r\n" );
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document.write( "  1		20		20\r\n" );
document.write( "  2		41		41\r\n" );
document.write( "  3		83		83\r\n" );
document.write( "  4		167		167\r\n" );
document.write( "  5				335\r\n" );
document.write( "  6				671\r\n" );
document.write( "  7				1343\r\n" );
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document.write( "First column is for index \"k\";\r\n" );
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document.write( "second column is the given numbers;\r\n" );
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document.write( "third column are the numbers calculated using the recursive formula.\r\n" );
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document.write( "From the Table, you see, that the formula correctly reproduces the given numbers.\r\n" );
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document.write( "Next, you see that the 7-th term is 1343, which does not coincide with your value.\r\n" );
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document.write( "So, your answer is INCORRECT.\r\n" );
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document.write( "Look for the error/errors in your computations.\r\n" );
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