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 A276876 #6 Sep 30 2016 13:22:57
%S A276876 1,2,3,4,7,8,9,12,13,14,15,18,19,20,23,24,25,26,29,30,31,34,35,36,37,
%T A276876 40,41,42,45,46,47,50,51,52,53,56,57,58,61,62,63,64,67,68,69,72,73,74,
%U A276876 75,78,79,80,83,84,85,88,89,90,91,94,95,96,99,100,101,102
%N A276876 Sums-complement of the Beatty sequence for 2e.
%C A276876 See A276871 for a definition of sums-complement and guide to related sequences.
%H A276876 <a href="/index/Be#Beatty">Index entries for sequences related to Beatty sequences</a>
%e A276876 The Beatty sequence for 2e is A276853 = (0,5,10,16,21,27,32,...), with difference sequence s = A276860 = (5,5,6,5,6,5,6,5,5,6,5,6,5,6,5,5,...). The sums s(j)+s(j+1)+...+s(k) include (5,6,7,10,11,16,17,...), with complement (1,2,3,4,7,8,9,12,...).
%t A276876 z = 500; r = 2E; b = Table[Floor[k*r], {k, 0, z}]; (* A276853 *)
%t A276876 t = Differences[b]; (* A276860 *)
%t A276876 c[k_, n_] := Sum[t[[i]], {i, n, n + k - 1}];
%t A276876 u[k_] := Union[Table[c[k, n], {n, 1, z - k + 1}]];
%t A276876 w = Flatten[Table[u[k], {k, 1, z}]]; Complement[Range[Max[w]], w] (* A276876 *)
%Y A276876 Cf. A276853, A276860, A276871.
%K A276876 nonn,easy
%O A276876 1,2
%A A276876 _Clark Kimberling_, Sep 27 2016