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 A100424 #6 Mar 30 2012 17:22:34
%S A100424 2,3,13,37,107,139,223,251,359,397,503,647,683,857,887,1033,1151,1249,
%T A100424 1291,1429,1493,1601,1667,1783,1831,2003,2053,2267,2377,2459,2593,
%U A100424 2677,2753,2801,2903,3119,3209,3347,3461,3557,3607,3727,3851,4079,4139,4243
%N A100424 A sieve transform applied three times to the positive integers.
%C A100424 The process is described in A099361. The first application of the sieve transform produces the prime numbers A000040. The second application yields sequence A099361. In principle, the sieve transform can be applied to any sequence of positive integers. For instance, the sieve transform of the positive even numbers is 2, 4, 8, 16,.... Also note that the transform can produce a finite sequence. See A100425 and A100426 for more examples.
%H A100424 T. D. Noe, <a href="/A100424/b100424.txt">Table of n, a(n) for n=1..1000</a>
%t A100424 SieveTransform[b_List] := Module[{d, nn=Length[b], a=b}, Do[d=a[[i]]; If[d>1, Do[a[[j]]=-1, {j, i+d, nn, d}]], {i, nn}]; DeleteCases[a, -1]]; SieveTransform[SieveTransform[SieveTransform[Range[2, 5000]]]]
%Y A100424 Cf. A099361, A100425, A100426.
%K A100424 nonn
%O A100424 1,1
%A A100424 _T. D. Noe_, Nov 19 2004