sequence of Zak Seidov needs extending

Jud McCranie j.mccranie at adelphia.net
Thu Feb 3 06:52:25 CET 2005


At 11:00 PM 2/2/2005, N. J. A. Sloane wrote:
>Dear Seqfans, Zak submitted this, but I can't use it
>without at least one more term. Can anyone extend it?
>
>
>%I A103359
>%S A103359 3,5,11
>%N A103359 Prime palindromic n such that pi(n) [A000720] is prime palindromic.
>%C A103359 No further terms with n less than 3000000. Palindromic pi(n) of 
>palindromic n A103357,A103358.
>%e A103359 pi(3)=2, pi(5)=3,pi(11)=5
>%Y A103359 Cf. A103357, A103358.
>%O A103359 0,1
>%K A103359 more,nonn,base,bref
>%A A103359 Zak Seidov (zakseidov(AT)yahoo.com), Feb 02 2005

My quick and dirty program doesn't find any more terms < 10^10.  Tomorrow I 
can modify it to go higher.

More terms are going to be hard to find.

pi(143787341) =  8114118, a palindrome, but not prime - is the closest I've 
found. (143787341 is a palindromic prime).

You might have to relax the condition that pi(n) be a prime, and just 
require it to be palindromic, while n is a palindromic prime.








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