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 A335702 #25 Aug 14 2020 16:15:26
%S A335702 0,1,2,4,5,8,12,16,17,18,24,32,34,40,48,50,56,64,65,72,80,81,88,96,
%T A335702 104,112,120,128,136,144,152,160,168,176,184,192,200,208,216,224,232,
%U A335702 240,248,256,257,258,260,261,272,273,274,288,290,304,306,320,321,336
%N A335702 A sequence connected with Rado’s explicit description of the Erdős-Rényi countable random graph.
%C A335702 It would be nice to have an explicit definition.
%H A335702 Rémy Sigrist, <a href="/A335702/b335702.txt">Table of n, a(n) for n = 1..10000</a>
%H A335702 Peter J. Cameron, <a href="https://cameroncounts.wordpress.com/2020/08/05/a-puzzle-3/">A Puzzle</a>, Blog, Aug 05 2020.
%H A335702 Peter J. Cameron, <a href="https://cameroncounts.wordpress.com/2020/08/13/puzzle-solution/">Puzzle Solution</a>, Blog, Aug 13 2020.
%o A335702 (PARI) S(n) = { my (s=[], i); while (n, i=valuation(n,2); s=concat(s,i); n-=2^i); s }
%o A335702 is(n) = my (s=S(n), z=if (#s, Set(concat(apply(S, s))), [])); setintersect(s, z)==[] \\ _Rémy Sigrist_, Aug 14 2020
%Y A335702 Cf. A133457.
%K A335702 nonn
%O A335702 1,3
%A A335702 _N. J. A. Sloane_, Aug 13 2020
%E A335702 More terms from _Rémy Sigrist_, Aug 14 2020