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%I #4 Mar 29 2015 11:41:31
%S 15,55,1555,125555,655555,1555555,145555555,355555555,8555555555,
%T 85555555555,155555555555,1555555555555,25555555555555,
%U 155555555555555,17555555555555555,25555555555555555,655555555555555555
%N Smallest semiprime ending in exactly n 5's.
%e a(3)=1555 is a term because 1555 is the smallest semiprime ending in exactly three 5's.
%t ssp[n_]:=Module[{k=0,c=FromDigits[Table[5,{n}]]},While[PrimeOmega[ k*10^n+ c]!=2,k++];k*10^n+c]; Array[ssp,20] (* _Harvey P. Dale_, Mar 29 2015 *)
%K base,nonn
%O 1,1
%A _Shyam Sunder Gupta_, May 12 2005
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