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 A350749 #8 Feb 16 2022 15:33:26
%S A350749 1,1,1,2,1,6,12,8,1,12,60,160,240,192,64,1,20,180,960,3360,8064,13440,
%T A350749 15360,11520,5120,1024,1,30,420,3640,21840,96096,320320,823680,
%U A350749 1647360,2562560,3075072,2795520,1863680,860160,245760,32768
%N A350749 Triangle read by rows: T(n,k) is the number of oriented graphs on n labeled nodes with k arcs, n >= 0, k = 0..n*(n-1)/2.
%H A350749 Andrew Howroyd, <a href="/A350749/b350749.txt">Table of n, a(n) for n = 0..1350</a> (rows 0..20)
%F A350749 T(n,k) = 2^k * binomial(n*(n-1)/2, k) = A013609(n*(n-1)/2, k).
%F A350749 T(n,k) = [y^k] (1+2*y)^(n*(n-1)/2).
%e A350749 Triangle begins:
%e A350749 [0] 1;
%e A350749 [1] 1;
%e A350749 [2] 1, 2;
%e A350749 [3] 1, 6, 12, 8;
%e A350749 [4] 1, 12, 60, 160, 240, 192, 64;
%e A350749 [5] 1, 20, 180, 960, 3360, 8064, 13440, 15360, 11520, 5120, 1024;
%e A350749 ...
%o A350749 (PARI) T(n,k) = 2^k * binomial(n*(n-1)/2, k)
%o A350749 (PARI)
%o A350749 row(n) = {Vecrev((1+2*y)^(n*(n-1)/2))}
%o A350749 { for(n=0, 6, print(row(n))) }
%Y A350749 Row sums are A047656.
%Y A350749 The unlabeled version is A350733.
%Y A350749 Cf. A013609, A350732 (weakly connected), A350731 (strongly connected).
%K A350749 nonn,tabf
%O A350749 0,4
%A A350749 _Andrew Howroyd_, Feb 15 2022