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 A183293 #4 Mar 30 2012 18:57:12
%S A183293 1,2,3,4,6,7,8,9,10,12,13,14,15,16,17,19,20,21,22,23,24,25,27,28,29,
%T A183293 30,31,32,33,34,36,37,38,39,40,41,42,43,44,46,47,48,49,50,51,52,53,54,
%U A183293 55,57,58,59,60,61,62,63,64,65,66,67,69,70,71,72,73,74,75,76,77,78,79,80,82,83,84,85,86,87,88,89
%N A183293 Complement of A056000.
%F A183293 (See the Mathematica code.)
%t A183293 a=1/2; b=9/2;
%t A183293 F[n_]:=a*n^2+b*n;
%t A183293 R[n_]:=(n/a+((b-1)/(2a))^2)^(1/2);
%t A183293 G[n_]:=n-1+Ceiling[R[n]-(b-1)/(2a)];
%t A183293 Table[F[n], {n,60}]
%t A183293 Table[G[n], {n,100}]
%Y A183293 Cf. A056000.
%K A183293 nonn
%O A183293 1,2
%A A183293 _Clark Kimberling_, Jan 03 2011