%I #9 Nov 29 2016 17:50:58
%S 22,25,27,32,33,35,52,55,57,72,75,77,112,115,117,132,133,135,172,175,
%T 177,192,195,213,217,219,231,232,235,237,243,247,253,259,261,267,273,
%U 279,289,292,295,297,312,315,319,323,329,341,343,361,371,372,375,377
%N Composite numbers that can be written as concatenation of two primes in decimal representation.
%C Subsequence of A066737.
%H Jean-Marc Falcoz, <a href="/A121609/b121609.txt">Table of n, a(n) for n = 1..11140</a>
%e A002808(249) = 315 = 31*10+5 = A000040(11)*10+A000040(3),
%e therefore 315 is a term: a(44) = 315;
%e A002808(252) = 319 = 3*100+19 = A000040(2)*100+A000040(8),
%e therefore 319 is a term: a(45) = 319.
%Y Cf. A121610, A105184, A121608.
%K nonn,base
%O 1,1
%A _Reinhard Zumkeller_, Aug 10 2006
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