%I #6 Sep 30 2013 17:01:51
%S 3000,30000,81000,30000,81000,810000,810000,1110000,1110000,810000,
%T 300000,300000,810000,1920000,810000,300000,300000,300000,300000,
%U 300000,1110000,8100000,8100000,11100000,8100000,8100000,3000000,11100000,8100000,8100000,8100000
%N Common difference in sets of 4 consecutive palindromic primes (palprimes) in arithmetic progression.
%e a(2)=30000 since (159202951, 159232951, 159262951, 159292951) is the second arithmetic progression of 4 consecutive palindromic primes with common difference = 30000.
%Y Cf. A059121.
%K nonn,base
%O 1,1
%A _Shyam Sunder Gupta_, Sep 29 2013