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 A109412 #2 Mar 30 2012 17:26:17 %S A109412 4,9,10,21,22,39,49,62,69,74,93,94,95,106,111,115,146,159,203,218,219, %T A109412 247,254,259,295,309,319,326,327,346,355,358,394,395,398,403,427,445, %U A109412 446,447,451,454,551,581,586,611,622,623,671,674,679,687,694,695,698 %N A109412 Semiprimes = one-term groups in the partition of the sequence of natural numbers A109411. %Y A109412 Cf. A109411, A109825, A109826. %K A109412 nonn %O A109412 1,1 %A A109412 _Zak Seidov_, Jul 03 2005