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%I #13 Mar 30 2012 17:31:31
%S 4,14,15,21,22,35,38,55,57,74,87,95,119,143,145,166,187,205,215,217,
%T 247,253,254,259,278,287,289,291,305,314,335,339,341,394,403,407,427,
%U 471,493,505,514,515,517,538,553,559,565,589,614,622,623,629,633,634,649
%N Semiprimes with semiprime "look and say" descriptions.
%C Semiprime analogous to A056815.
%e 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 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 Cf. A001358, A056815.
%K easy,nonn
%O 1,1
%A _Robert G. Wilson v_, Jan 27 2012
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