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A350795 Triangle read by rows: T(n,k) is the number of digraphs on n unlabeled nodes with k arcs and a global source and sink, n >= 1, k = 0..max(1,n-1)*(n-2)+1.

%I A350795 #8 Jan 29 2022 22:31:11
%S A350795 1,0,1,0,0,1,1,0,0,0,1,6,8,4,1,0,0,0,0,1,16,70,140,159,113,53,17,4,1,
%T A350795 0,0,0,0,0,1,33,313,1439,3941,7297,9750,9840,7717,4788,2377,946,309,
%U A350795 80,18,4,1,0,0,0,0,0,0,1,58,998,8447,43269,152135,396011
%N A350795 Triangle read by rows: T(n,k) is the number of digraphs on n unlabeled nodes with k arcs and a global source and sink, n >= 1, k = 0..max(1,n-1)*(n-2)+1.
%H A350795 Andrew Howroyd, <a href="/A350795/b350795.txt">Table of n, a(n) for n = 1..2319</a> (rows 1..20)
%e A350795 Triangle begins:
%e A350795   [1] 1;
%e A350795   [2] 0, 1;
%e A350795   [3] 0, 0, 1, 1;
%e A350795   [4] 0, 0, 0, 1, 6,  8,  4,   1;
%e A350795   [5] 0, 0, 0, 0, 1, 16, 70, 140, 159, 113, 53, 17, 4, 1;
%e A350795   ...
%o A350795 (PARI) \\ See PARI link in A350794 for program code.
%o A350795 { my(A=A350795triang(5)); for(n=1, #A, print(A[n])) }
%Y A350795 Row sums are A350794.
%Y A350795 Column sums are A350796.
%Y A350795 The labeled version is A350791.
%Y A350795 Cf. A057277, A057278, A350797.
%K A350795 nonn,tabf
%O A350795 1,12
%A A350795 _Andrew Howroyd_, Jan 21 2022