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 A155029 #10 Mar 07 2021 17:43:32
%S A155029 1,0,1,0,1,1,0,0,1,1,0,1,1,1,1,0,0,0,1,1,1,0,1,1,1,1,1,1,0,0,1,0,1,1,
%T A155029 1,1,0,1,0,1,1,1,1,1,1,0,0,1,1,0,1,1,1,1,1,0,1,1,1,1,1,1,1,1,1,1,0,0,
%U A155029 0,0,1,0,1,1,1,1,1,1,0,1,1,1,1,1,1,1,1,1,1,1,1
%N A155029 Complement to A051731 with the identity matrix A023531 included.
%H A155029 G. C. Greubel, <a href="/A155029/b155029.txt">Rows n = 1..30 of the triangle, flattened</a>
%F A155029 T(n, k) = 0 if n==0 (mod k) otherwise 1 with T(n, n) = 1 and T(n, 1) = 0. - _G. C. Greubel_, Mar 07 2021
%e A155029 Table begins:
%e A155029 1;
%e A155029 0, 1;
%e A155029 0, 1, 1;
%e A155029 0, 0, 1, 1;
%e A155029 0, 1, 1, 1, 1;
%e A155029 0, 0, 0, 1, 1, 1;
%e A155029 0, 1, 1, 1, 1, 1, 1;
%e A155029 0, 0, 1, 0, 1, 1, 1, 1;
%e A155029 0, 1, 0, 1, 1, 1, 1, 1, 1;
%t A155029 Table[If[k==n, 1, If[k==0, 0, If[Mod[n, k]==0, 0, 1]]], {n, 20}, {k, n}]//Flatten (* _G. C. Greubel_, Mar 07 2021 *)
%o A155029 (Sage) flatten([[1 if k==n else 0 if (k==0 or n%k==0) else 1 for k in [1..n]] for n in [1..20]]) # _G. C. Greubel_, Mar 07 2021
%o A155029 (Magma) [k eq n select 1 else (k eq 0 or n mod k eq 0) select 0 else 1: k in [1..n], n in [1..20]]; // _G. C. Greubel_, Mar 07 2021
%Y A155029 Cf. A023531, A051731, A155031.
%K A155029 nonn,tabl
%O A155029 1,1
%A A155029 _Mats Granvik_, Jan 19 2009