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document.write( "Answer. The smallest positive integer that has exactly 6 divisors is 12 =
.\r
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document.write( "Solution.\r
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document.write( "1. For integer number N =
, where p is a prime number and
is an integer exponent (index), \r\n" );
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document.write( " the number of divisors is
.\r\n" );
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document.write( " You can easily check it: the divisors are 1, p,
, . . . ,
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document.write( "2. For integer number N =
, where p, q, . . . , r are prime divisors and
,
, . . . ,
are integer exponents (indexes) \r\n" );
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document.write( " the number of divisors is
.\r\n" );
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document.write( "3. From these facts, you can easily obtain the answer.\r\n" );
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document.write( " Notice that 6 = 2*3.\r\n" );
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document.write( " It is easy to list those divisors: 1, 2, 4, 3, 6, 12.\r\n" );
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