document.write( "Question 749860: Dear Tutor,
\n" ); document.write( "which is the next number in this row: 2, 6, 30, 168, 1320? Thank you very much and
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\n" ); document.write( "\n" ); document.write( "Decebal Paltanea
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Algebra.Com's Answer #456192 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "It is a trial and error process.  We compare it term by term\r\n" );
document.write( "with standard sequences that we are familiar with, and hopefully\r\n" );
document.write( "we will find one that it compares nicely with.\r\n" );
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document.write( "2,   6, 30, 168, 1320\r\n" );
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document.write( "After much trial and error I finally tried comparing\r\n" );
document.write( "it term by term with the sequence of factorials: \r\n" );
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document.write( "1!, 2!, 3!,  4!,   5!, or\r\n" );
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document.write( "1,   2,  6,  24,  120\r\n" );
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document.write( "\"2%2F1\", \"6%2F2\", \"30%2F6\", \"168%2F24\",  \"1320%2F120\"\r\n" );
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document.write( "2,   3,  5,   7,   11\r\n" );
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document.write( "That is the sequence of prime numbers.\r\n" );
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document.write( "So the formula for the nth term is\r\n" );
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document.write( "an =  n!(nth_prime_number)\r\n" );
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document.write( "The 6th prime number is 13, so it will be 6!×13 = 9360\r\n" );
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document.write( "Edwin
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