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 A203815 Primes which are the decimal concatenation of two squares in more than one way. 0
 14449, 4651249, 14592449, 25281961, 64516961, 144552049, 4963984001, 10241442401, 121828921681, 1089936421201, 1589776384961, 4640334443681, 19713620187049, 25593280441009, 81105458016049, 121521961692601, 445309309225961 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Subsequence of A167535. LINKS EXAMPLE a(1) = 14449 = the concatenation of 12^2 and 7^2 and of 38^2 and 3^2. a(5) = 64516961 = the concatenation of 8^2 and 719^2 and of 254^2 and 31^2. MATHEMATICA K[m_Integer, n_Integer] := n+m*10^IntegerLength[n]; k=-1; V={}; g=5000000; W={}; While[k10 (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

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Last modified July 30 07:41 EDT 2021. Contains 346348 sequences. (Running on oeis4.)