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%I #8 Jan 15 2022 12:29:29
%S 1,0,0,0,0,0,1,0,0,0,0,1,2,1,0,0,0,0,0,1,5,18,27,19,6,0,0,0,0,0,0,1,8,
%T 80,333,765,1122,1049,622,217,35,0,0,0,0,0,0,0,1,12,221,1875,8971,
%U 28449,63845,105556,130935,122607,85926,43868,15506,3403,353
%N Triangle read by rows: T(n,k) is the number of strongly connected oriented graphs on n unlabeled nodes with k arcs, n >= 1, k = 0..n*(n-1)/2.
%H Andrew Howroyd, <a href="/A350750/b350750.txt">Table of n, a(n) for n = 1..1350</a> (rows 1..20)
%e Triangle begins:
%e [1] 1;
%e [2] 0, 0;
%e [3] 0, 0, 0, 1;
%e [4] 0, 0, 0, 0, 1, 2, 1;
%e [5] 0, 0, 0, 0, 0, 1, 5, 18, 27, 19, 6;
%e [6] 0, 0, 0, 0, 0, 0, 1, 8, 80, 333, 765, 1122, 1049, 622, 217, 35;
%e ...
%o (PARI) \\ See PARI link in A350489 for program code.
%o { my(A=A350750rows(7)); for(n=1, #A, print(A[n])) }
%Y Row sums are A350489.
%Y Column sums are A350751.
%Y The labeled version is A350731.
%Y Cf. A057276 (digraphs), A350733, A350734.
%K nonn,tabf
%O 1,13
%A _Andrew Howroyd_, Jan 13 2022
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