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 A277737 #15 Nov 07 2016 11:29:32 %S A277737 2,7,9,11,15,19,24,26,31,33,38,40,42,46,51,53,55,59,64,66,68,72,76,81, %T A277737 83,88,90,92,96,100,105,107,112,114,116,120,124,129,131,136,138,143, %U A277737 145,147,151,156,158,160,164,168,173,175,180,182,187,189,191,195,200,202,204,208,212,217,219,224,226 %N A277737 Positions of 1's in A277735. %C A277737 {A277736, A277737, A277738} forms a three-way partition of the positive integers, similar to {A003144, A003145, A003146}. %H A277737 N. J. A. Sloane, <a href="/A277737/b277737.txt">Table of n, a(n) for n = 1..19513</a> %p A277737 with(ListTools); %p A277737 T:=proc(S) Flatten(subs( {0=[0,1], 1=[2,0], 2=[0]}, S)); end; %p A277737 S:=[0]; %p A277737 for n from 1 to 14 do S:=T(S); od: %p A277737 S; # A277735 %p A277737 p0:=[]: p1:=[]: p2:=[]: %p A277737 for i from 1 to nops(S) do %p A277737 j:=S[i]; %p A277737 if j=0 then p0:=[op(p0),i]; %p A277737 elif j=1 then p1:=[op(p1),i]; %p A277737 else p2:=[op(p2),i]; fi: od: %p A277737 p0; # A277736 %p A277737 p1; # A277737 %p A277737 p2: # A277738 %Y A277737 Cf. A277735, A277736, A277738. %Y A277737 Cf. also A003144, A003145, A003146. %K A277737 nonn %O A277737 1,1 %A A277737 _N. J. A. Sloane_, Nov 07 2016