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 A138150 #5 Nov 28 2018 15:22:24
%S A138150 0,0,1,1,1,0,0,0,0,0,1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,
%T A138150 1,1,1,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,
%U A138150 1,1,1,1,1,1,1,1,1
%N A138150 n-th run has length n-th prime, with digits 0 and 1 only, starting with 0.
%e A138150 .n ..... Run ....................... Length
%e A138150 .1 ..... 0,0 ....................... 2
%e A138150 .2 ..... 1,1,1 ..................... 3
%e A138150 .3 ..... 0,0,0,0,0 ................. 5
%e A138150 .4 ..... 1,1,1,1,1,1,1 ............. 7
%e A138150 .5 ..... 0,0,0,0,0,0,0,0,0,0,0 ..... 11
%t A138150 With[{nn=11},Riffle[Table[PadRight[{},Prime[n],0],{n,1,nn,2}],Table[ PadRight[ {},Prime[n+1],1],{n,1,nn,2}]]//Flatten] (* _Harvey P. Dale_, Nov 28 2018 *)
%Y A138150 Cf. A000040, A057212.
%K A138150 easy,nonn
%O A138150 1,1
%A A138150 _Omar E. Pol_, Mar 29 2008