a(n) = A098916(n+2) + (1-n) * A067318(n).

A121723

a(n) = A098916(n+2) + (1-n) * A067318(n).

Terms

    a(0) =0a(1) =3a(2) =22a(3) =150a(4) =1096a(5) =8820a(6) =78408a(7) =767088a(8) =8212608a(9) =95657760a(10) =1205438400a(11) =16350871680a(12) =237633108480

External references