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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.

A204541 Semiprimes with semiprime "look and say" descriptions.

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%I A204541 #13 Mar 30 2012 17:31:31
%S A204541 4,14,15,21,22,35,38,55,57,74,87,95,119,143,145,166,187,205,215,217,
%T A204541 247,253,254,259,278,287,289,291,305,314,335,339,341,394,403,407,427,
%U A204541 471,493,505,514,515,517,538,553,559,565,589,614,622,623,629,633,634,649
%N A204541 Semiprimes with semiprime "look and say" descriptions.
%C A204541 Semiprime analogous to A056815.
%e A204541 14 is in the sequence because 14 is a semiprime (2*7) and its "Look and Say", 1114 is also a semiprime (2*557).
%t A204541 LookAndSayA[n_] := FromDigits@ Flatten@ IntegerDigits@ Flatten[ Through[ {Length, First}[#]] & /@ Split@ IntegerDigits@ n]; semiPrimeQ[n_] := Plus @@ Last /@ FactorInteger@ n == 2; Select[ Range@ 650, semiPrimeQ@# && semiPrimeQ@ LookAndSayA@# &]
%Y A204541 Cf. A001358, A056815.
%K A204541 easy,nonn
%O A204541 1,1
%A A204541 _Robert G. Wilson v_, Jan 27 2012