This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A203815 #13 Mar 31 2012 10:32:52
%S A203815 14449,4651249,14592449,25281961,64516961,144552049,4963984001,
%T A203815 10241442401,121828921681,1089936421201,1589776384961,4640334443681,
%U A203815 19713620187049,25593280441009,81105458016049,121521961692601,445309309225961
%N A203815 Primes which are the decimal concatenation of two squares in more than one way.
%C A203815 Subsequence of A167535.
%e A203815 a(1) = 14449 = the concatenation of 12^2 and 7^2 and of 38^2 and 3^2.
%e A203815 a(5) = 64516961 = the concatenation of 8^2 and 719^2 and of 254^2 and 31^2.
%t A203815 K[m_Integer, n_Integer] := n+m*10^IntegerLength[n]; k=-1; V={}; g=5000000; W={}; While[k<g, k++; m=2 k+1; n=0; While[n<2 g, n++; a=K[n^2, m^2]; If[a>10 (2 g)^2, n=2 g, If[PrimeQ[a], V={V, a}]]]]; V=Flatten[V]; W1=Sort[V]; W2=Union[V](*= A167535*); i=0; While[i<Length[W1]-1, i++; If[W1[[i+1]]==W1[[i]], W=Append[W, W1[[i]]]]]; Union[W]
%Y A203815 Cf. A167535.
%K A203815 nonn,base
%O A203815 1,1
%A A203815 _Emmanuel Vantieghem_, Jan 06 2012