Number of semi-meanders of order n with 6 components.

Terms

a(0) =1a(1) =6a(2) =32a(3) =152a(4) =690a(5) =3028a(6) =12996a(7) =54812a(8) =228284a(9) =939148a(10) =3833076a(11) =15487428a(12) =62244564a(13) =247973928a(14) =984221764a(15) =3876113404a(16) =15223550024a(17) =59379645924a(18) =231124139318a(19) =894157177372