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 A155506 #2 Mar 30 2012 17:37:58
%S A155506 2,4,8,14,22,32,42,54,68,82,98,116,134,154,176,200,224,250,278,306,
%T A155506 336,368,400,434,470,508,546,586,628,670,714,760,808,856,906,958,1010,
%U A155506 1064,1120,1178,1236,1296,1358,1420,1484,1550,1616,1684,1754,1826,1898,1972
%N A155506 An eigensequence of the (L)-sieve transform (LST); LST(A)=A/2.
%C A155506 See A152009 for the definition of the (L)-sieve transform.
%C A155506 As noted in A152009, the sequence T of triangular numbers {1,3,6,...,n(n+1)/2,...} =A000217 is also an eigensequence of the (L)-sieve transform (LST), satisfying LST(T)=T.
%Y A155506 A000217, A152009
%K A155506 eigen,nonn
%O A155506 1,1
%A A155506 _John W. Layman_, Jan 23 2009