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%I #1 Feb 19 2004 03:00:00
%S 5,53,59,67,137,179,211,223,239,263,359,541,593,613,631,653,659,757,
%T 809,977,997,1009,1109,1129,1237,1399,1559,1783,1931,1979,1993,2309,
%U 2339,2347,2411,2683,2879,3061,3203,3271,3613,3643,3767,4001
%N Primes which when concatenated with the previous prime form a new prime.
%F If isprime(p(n) & p(n-1)) then sequence.add(p(n))
%e a(2) = 53 because 53 concatenated with the preceding prime (47) yields 5347 which is also prime.
%Y Cf. A088784.
%K base,nonn
%O 1,1
%A Chuck Seggelin (barkeep(AT)plasteredDragon.com), Oct 15 2003