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%I #10 Feb 05 2015 07:12:03
%S 1,0,2,1,0,0,12,20,15,6,1,0,0,0,104,426,768,920,792,495,220,66,12,1,0,
%T 0,0,0,1160,9184,32420,73000,123425,166860,184426,167900,125965,77520,
%U 38760,15504,4845,1140,190,20,1
%N 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).
%H V. Jovovic and G. Kilibarda, <a href="http://dx.doi.org/10.1016/S0012-365X(00)00112-6">Enumeration of labeled quasi-initially connected digraphs</a>, Discrete Math., 224 (2000), 151-163.
%e Triangle starts:
%e 1;
%e 0,2,1;
%e 0,0,12,20,15,6,1;
%e 0,0,0,104,426,768,920,792,495,220,66,12,1;
%e ...
%e Number of digraphs with a quasi-source on 3 labeled nodes is 54=12+20+15+6+1.
%Y Row sums give A049414. Cf. A057270, A057271, A057273-A057279.
%K nonn,tabf
%O 1,3
%A _Vladeta Jovovic_, Goran Kilibarda, Sep 14 2000
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