184426

Appears in sequences

• Triangular array giving number of labeled digraphs on n unisolated nodes and k=0..n*(n-1) arcs.at n=34A054547
• Triangle T(n,k) of number of digraphs with a quasi-source on n labeled nodes and with k arcs, k=0,1,..,n*(n-1).at n=34A057272
• Triangular array T(n,k) giving number of weakly connected digraphs with n labeled nodes and k arcs (n >= 1, 0 <= k <= n(n-1)).at n=34A062735
• G.f. satisfies: A(x) = Sum_{n>=0} x^n * ( (A(x)^n + A(-x)^n)/2 )^n.at n=11A212961