<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META http-equiv=Content-Type content="text/html; charset=iso-2022-jp">
<META content="MSHTML 6.00.2900.2180" name=GENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY bgColor=#ffffff>
<DIV><FONT face="MS UI Gothic"> Richard Guy wrote :
</FONT></DIV>
<DIV><FONT face="MS UI Gothic"> >Perhaps no one has yet
done an<BR> >exhaustive search as far as that? Is
this such<BR> >a hard job with modern
technology? </FONT></DIV>
<DIV><FONT face="MS UI Gothic"></FONT> </DIV>
<DIV><FONT face="MS UI Gothic"> An exhaustive search has been
done below 10^12.</FONT></DIV>
<DIV><FONT face="MS UI Gothic"> See Jan Pedersen's
site.</FONT></DIV>
<DIV><FONT face="MS UI Gothic"></FONT> </DIV>
<DIV><FONT face="MS UI Gothic"> <FONT size=2><A
href="http://amicable.homepage.dk/knwnu2.htm">http://amicable.homepage.dk/knwnu2.htm</A></FONT></FONT></DIV>
<DIV><FONT face="MS UI Gothic"></FONT> </DIV>
<DIV><FONT face="MS UI Gothic"> >E.g. 114 has unitary
divisors 1, (2,57), (3,38) and<BR>(6,19), apart from 114 itself. Their sum
is 126, whose unitary divisors < 126 are 1, (2,63), (7,18), (9,14) whose sum
is 114. </FONT></DIV>
<DIV><FONT face="MS UI Gothic"> </FONT></DIV>
<DIV><FONT face="MS UI Gothic"> Thanks for the explanation of
Unitary AP.</FONT></DIV>
<DIV><FONT face="MS UI Gothic"><FONT size=2></FONT><FONT size=2></FONT><FONT
size=2></FONT><FONT size=2></FONT><FONT
size=2></FONT><BR> </DIV></FONT><FONT face="MS UI Gothic"></FONT>
<DIV><FONT face="MS UI Gothic" size=2></FONT> </DIV>
<DIV><FONT face="MS UI Gothic" size=2> <FONT size=3>
Yasutoshi</FONT></FONT></DIV>
<DIV><FONT face="MS UI Gothic" size=2><FONT size=3> </FONT>
</FONT></DIV></BODY></HTML>