document.write( "Question 1000049: how many positive integers from 1 to 400 inclusive have exactly three positive integral factors? \n" ); document.write( "

Algebra.Com's Answer #617676 by Alan3354(69443) $\"\"$ $\"About$

You can put this solution on YOUR website!
how many positive integers from 1 to 400 inclusive have exactly three positive integral factors?
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\n" ); document.write( "If 1 is not included as a factor:
\n" ); document.write( "2*2*5
\n" ); document.write( "2*2*5
\n" ); document.write( "2*2*7
\n" ); document.write( "2*2*11
\n" ); document.write( "2*2*13
\n" ); document.write( "2*2*17
\n" ); document.write( "2*2*19
\n" ); document.write( "2*2*23
\n" ); document.write( "2*2*29
\n" ); document.write( "2*2*31
\n" ); document.write( "2*2*37
\n" ); document.write( "2*2*47
\n" ); document.write( "2*2*53
\n" ); document.write( "2*2*59
\n" ); document.write( "2*2*61
\n" ); document.write( "2*2*67
\n" ); document.write( "2*2*71
\n" ); document.write( "2*2*73
\n" ); document.write( "2*2*79
\n" ); document.write( "2*2*83
\n" ); document.write( "2*2*89
\n" ); document.write( "2*2*97
\n" ); document.write( "------
\n" ); document.write( "2*3*5
\n" ); document.write( "2*3*7
\n" ); document.write( "2*3*11
\n" ); document.write( "2*3*13
\n" ); document.write( "2*3*17
\n" ); document.write( "2*3*19
\n" ); document.write( "2*3*23
\n" ); document.write( "2*3*29
\n" ); document.write( "2*3*31
\n" ); document.write( "2*3*37
\n" ); document.write( "2*3*47
\n" ); document.write( "2*3*53
\n" ); document.write( "2*3*59
\n" ); document.write( "2*3*61
\n" ); document.write( "---
\n" ); document.write( "2*5*5
\n" ); document.write( "2*5*7
\n" ); document.write( "2*5*11
\n" ); document.write( "2*5*13
\n" ); document.write( "2*5*17
\n" ); document.write( "2*5*19
\n" ); document.write( "2*5*23
\n" ); document.write( "2*5*29
\n" ); document.write( "2*5*31
\n" ); document.write( "2*5*37
\n" ); document.write( "------
\n" ); document.write( "2*7*7
\n" ); document.write( "2*7*11
\n" ); document.write( "2*7*13
\n" ); document.write( "2*7*17
\n" ); document.write( "2*7*19
\n" ); document.write( "2*7*23
\n" ); document.write( "------
\n" ); document.write( "2*11*11
\n" ); document.write( "2*11*13
\n" ); document.write( "2*11*17
\n" ); document.write( "------
\n" ); document.write( "3*5*5
\n" ); document.write( "3*5*7
\n" ); document.write( "3*5*11
\n" ); document.write( "3*5*13
\n" ); document.write( "3*5*17
\n" ); document.write( "3*5*19
\n" ); document.write( "3*5*23
\n" ); document.write( "------
\n" ); document.write( "3*7*7
\n" ); document.write( "3*7*11
\n" ); document.write( "3*7*13
\n" ); document.write( "3*7*17
\n" ); document.write( "3*7*19
\n" ); document.write( "------
\n" ); document.write( "5*7*7
\n" ); document.write( "5*7*11
\n" ); document.write( "------
\n" ); document.write( "You can count them.
\n" ); document.write( " \n" ); document.write( "

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