Number of directed loopless multigraphs with n arcs.

A052170

Number of directed loopless multigraphs with n arcs.

Terms

    a(0) =1a(1) =1a(2) =6a(3) =24a(4) =130a(5) =688a(6) =4211a(7) =26840a(8) =184153a(9) =1328155a(10) =10078617a(11) =79926478a(12) =660616432a(13) =5671793248a(14) =50459837996a(15) =464139053799

External references