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Number of unlabeled digraphs with n arcs and a global source (or sink).
5

%I #6 Jan 22 2022 18:30:11

%S 1,1,2,6,21,84,387,1953,10802,64267,408489,2750686,19518841,145236878,

%T 1128884559,9135566309,76758391212,667993213393,6008434514996,

%U 55755719348210,532896254763646,5238211003916685,52885470406233727,547751388283907208,5813693205313803535,63170000832869927871

%N Number of unlabeled digraphs with n arcs and a global source (or sink).

%o (PARI) A350798seq(15) \\ See PARI link in A350794 for program code.

%Y Column sums of A350797.

%Y Cf. A350360, A350752, A350796, A350906, A350907.

%K nonn

%O 0,3

%A _Andrew Howroyd_, Jan 21 2022