[seqfan] Primes by concatenation

[Eric Angelini]

Hello SeqFans,
if I'm not wrong, S is not in the OEIS:
-- S starts with a(1)=1 then S is extended with the smallest integer a(n)
not yet present in S such that the
concatenation < a(n-1); a(n) > or < a(n); a(n-1) >
is prime.

S=1,3,2,9,5,21,4,7,6,13,10,19,16,27,8,11,15,23,12,17,20,29,32,59,14,...

Primes produced by said concatenation  are:
13,23,29,59,521,421,47,67,613,1013,1019,1619,1627,827,811,1511,...

I guess S is a permutation of N (1,2,3,4,5,... oo)
Best,
É.