Number of oriented series-parallel networks with n elements and without multiple unit elements in parallel.

A339290

Number of oriented series-parallel networks with n elements and without multiple unit elements in parallel.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =5a(4) =13a(5) =36a(6) =103a(7) =306a(8) =930a(9) =2887a(10) =9100a(11) =29082a(12) =93951a(13) =306414a(14) =1007361a(15) =3335088a(16) =11108986a(17) =37203873a(18) =125193694a(19) =423099557a(20) =1435427202a(21) =4886975378a(22) =16690971648a(23) =57172387872a(24) =196358421066a(25) =676050576441

External references