[seqfan] Fwd: A new 17350 digit Symmetric Prime

[jean-paul allouche]

Dear all

FYI
best
jpa

-------- Message transféré --------
Sujet : 	A new 17350 digit Symmetric Prime
Date : 	Mon, 20 Jul 2015 21:13:24 -0500
De : 	Shyam Sunder Gupta <guptass at REDIFFMAIL.COM>
Répondre à : 	Number Theory List <NMBRTHRY at LISTSERV.NODAK.EDU>, Shyam 
Sunder Gupta <guptass at REDIFFMAIL.COM>
Pour : 	NMBRTHRY at LISTSERV.NODAK.EDU



Dear number theorists,

    Here I report a new 17350 digit Symmetric Prime.
  In the sequence of numbers 1,121,12321,1234321,123454321...( OEIS A173426 ), whose nth number is

  S(n) = 123 ... (n-1)n(n-1) .. .321 , the only known prime till date is a 20 digit prime i.e. 12345678910987654321.
  I have found a new 17350 digit  Prime in the above sequence.
  This prime is n=2446th term in the sequence  given above:
  
  This can be denoted in short as 1234567..244524462445......765321

  After announcing this prime , doubts about non existence of primes in the above sequence other than the one already known (i.e. 12345678910987654321) shall vanish.
  Though I have not certified this prime as yet, but I have checked this prime for primality exhaustively including with PrimeQ Mathematica function.
  This prime is very interesting and can easily be remembered. This  can be termed as a Platinum prime.

  Shyam Sunder Gupta
www.shyamsundergupta.com