Generalized tangent numbers.

Terms

a(0) =2a(1) =16a(2) =136a(3) =1232a(4) =12096a(5) =129024a(6) =1491840a(7) =18627840a(8) =250145280a(9) =3597834240a(10) =55212917760a(11) =900842342400