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<TITLE>[seqfan] INTERRUPTION DE SERVICE - MAILING LIST HIATUS</TITLE>
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<DIV id=idOWAReplyText9611 dir=ltr>
<DIV dir=ltr><FONT face=Arial color=#000000 size=2>Sorry for the bad header --
and the old "tail"... I'm not working on my "normal" computer and quite
confused :-/</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2>Best,</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2>É.</FONT></DIV></DIV>
<DIV dir=ltr><BR>
<HR tabIndex=-1>
<BR></DIV>
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<DIV id=idOWAReplyText34525 dir=ltr>
<DIV dir=ltr><FONT face="Courier New" color=#000000 size=2>Hello
SeqFans,</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>could someone check and compute a
hundred terms or so of the seq below?</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New"
size=2>4,6,9,21,22,25,33,39,46,49,51,54,...</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>Integers n whose "ordered
concatenation" of all divisors (except 1 and n) is a prime.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2> n
div. prime</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2> 4 ->
1,2,4 -> 2</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2> 6 -> 1,2,3,6
-> 23</FONT></DIV></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2> 9 -> 1,3,9
-> 3</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>21 -> 1,3,7,21
-> 37</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>22 -> 1,2,11,22 ->
211</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>25 -> 1,5,25
-> 5</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>33 -> 1,3,11,33 ->
311</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>39 -> 1,3,13,39 ->
313</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>...</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>26 is not a member :</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>26 -> 1,2,13,26 -> 213 ->
1,3,71,213 -> 371 -> 1,7,53,371 -> 753 -> 1,3,251,753 -> 3251 is
prime</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>but 753 will be a
member.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>I like 54:</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>54 -> 1,2,3,6,9,18,27,54 ->
23691827 prime</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>Best,</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>É.</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>-----</FONT></DIV>
<DIV dir=ltr> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>(I've used Magma to compute the
factorization, plus Edwin Clarkk's advice:</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>> [Math-Fun]</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>></FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>> (...)</FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2>> Use for example the command
Divisors(12345678); at this site<BR>><BR>> <A
href="/exchweb/bin/redir.asp?URL=http://magma.maths.usyd.edu.au/calc/"
target=_blank>http://magma.maths.usyd.edu.au/calc/</A><BR>><BR>> and click
on evaluate. You will get<BR>><BR>> [ 1, 2, 3, 6, 9, 18, 47, 94, 141, 282,
423, 846, 14593, 29186, 43779,<BR>> 87558, 131337, 262674, 685871, 1371742,
2057613, 4115226, 6172839,<BR>> 12345678 ]<BR>><BR>> Total time: 0.350
seconds, Total memory usage: 6.46MB<BR><BR></FONT></DIV>
<DIV dir=ltr><FONT face="Courier New" size=2></FONT> </DIV>
<DIV dir=ltr><FONT size=+0><FONT face="Courier New"
size=2></FONT> </DIV></FONT></DIV>
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