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

A339293

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

Terms

    a(0) =1a(1) =1a(2) =2a(3) =3a(4) =5a(5) =10a(6) =17a(7) =34a(8) =62a(9) =123a(10) =230a(11) =462a(12) =879a(13) =1772a(14) =3427a(15) =6930a(16) =13562a(17) =27501a(18) =54338a(19) =110449a(20) =219962a(21) =448054a(22) =898146a(23) =1833248a(24) =3694974a(25) =7556473a(26) =15301319a(27) =31349605a(28) =63734241a(29) =130807801

External references