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a(1)=2, a(2)=23; thereafter a(n) is the smallest prime which begins with the concatenation a(n-2)a(n-1).
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%I #20 Jan 01 2015 20:11:59

%S 2,23,223,2322337,223232233717,232233722323223371711,

%T 223232233717232233722323223371711159,

%U 232233722323223371711223232233717232233722323223371711159007

%N a(1)=2, a(2)=23; thereafter a(n) is the smallest prime which begins with the concatenation a(n-2)a(n-1).

%C a(4) = 2322337 == 23, 223, 37

%H Alois P. Heinz, <a href="/A252016/b252016.txt">Table of n, a(n) for n = 1..13</a>

%Y Cf. A240563.

%K nonn,base

%O 1,1

%A _Giovanni Teofilatto_, Dec 13 2014

%E a(6)-a(8) from _Alois P. Heinz_, Jan 01 2015