On sequence nXn where x equal 09,18,27,36,45,54,63,72,81,90

[Ed Pegg Jr]

On sequence nXn where x equal 09,18,27,36,45,54,63,72,81,90

In the example you give, the numbers have a common difference
of 90.  By chosing different n, the common difference can be
900, 9000, and so on.  In order for all of these to be prime,
none of them can be divisible by 7.  From there, a Modulus
argument can be made to prove impossibility, but I don't have
the time to write it up in full just this second.

Differences[A_List] :=Drop[A,1] - Drop[A,-1]

Differences[{1091,1181,1271,1361,1451,1541,1631,1721,1811,1901}]

{90,90,90,90,90,90,90,90,90}

Karima MOUSSAOUI wrote:

 > Dear,
 >
 > Is not arithmetixc progression
 >
 > example
 >
 > 1091, 1181, 1271, 1361 , ... is not arithmetic progression
 >
 > 
 >
 > Thanks