Number of oriented series-parallel networks with n colored elements using exactly 2 colors.

A339227

Number of oriented series-parallel networks with n colored elements using exactly 2 colors.

Terms

    a(0) =0a(1) =3a(2) =22a(3) =146a(4) =970a(5) =6601a(6) =46012a(7) =328188a(8) =2387498a(9) =17666752a(10) =132631060a(11) =1008068661a(12) =7743145556a(13) =60019505338a(14) =468911161556

External references