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<DIV><FONT face=Arial size=2>Dear Jr, Ed Pegg</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>You have right</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thank you very Much</FONT></DIV>
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<DIV><FONT face=Arial size=2>Thanks</FONT></DIV>
<DIV><BR><BR>>>> Ed Pegg Jr <edp@wolfram.com> 02/23 7:13
>>><BR>On sequence nXn where x equal
09,18,27,36,45,54,63,72,81,90<BR><BR>In the example you give, the numbers have a
common difference<BR>of 90. By chosing different n, the common difference
can be<BR>900, 9000, and so on. In order for all of these to be
prime,<BR>none of them can be divisible by 7. From there, a
Modulus<BR>argument can be made to prove impossibility, but I don't have<BR>the
time to write it up in full just this second.<BR><BR>Differences[A_List]
:=Drop[A,1] -
Drop[A,-1]<BR><BR>Differences[{1091,1181,1271,1361,1451,1541,1631,1721,1811,1901}]<BR><BR>{90,90,90,90,90,90,90,90,90}<BR><BR>Karima
MOUSSAOUI wrote:<BR><BR>> Dear,<BR>><BR>> Is not arithmetixc
progression<BR>><BR>> example<BR>><BR>> 1091, 1181, 1271, 1361 , ...
is not arithmetic progression<BR>><BR>> <BR>><BR>>
Thanks<BR><BR><BR></DIV></BODY></HTML>