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 A190664 #9 Mar 30 2012 18:35:55
%S A190664 21,55,39,51,203,87,111,123,371,183,335,395,623,267,291,327,1703,635,
%T A190664 411,1043,447,815,1211,543,591,7223,1055,2951,1115,687,771,1883,831,
%U A190664 843,4043,1535,951,1655,1011,1047,12059,1835,2723,1167,1191,1203,4763,1347
%N A190664 Least semiprime whose prime factors differ by 2*prime(n).
%F A190664 a(n) = A073703(n) * A073704(n).
%e A190664 a(5) = 203 because 203 = 7*29, and 29 - 7 = 22 = 2*11 = 2*prime(5).
%t A190664 f[n_] := Block[{p=3}, While[! PrimeQ[p+2*Prime[n]], p=NextPrime[p]]; p*(p+2*Prime[n])]; Table[f[n], {n, 1, 60}]
%Y A190664 Cf. A073703, A073704.
%K A190664 nonn
%O A190664 1,1
%A A190664 _Michel Lagneau_, May 16 2011