Almost-convex polygons of perimeter 2n on square lattice.

A007222

Almost-convex polygons of perimeter 2n on square lattice.

Terms

    a(0) =28a(1) =1468a(2) =34680a(3) =535452a(4) =6302296a(5) =61400920a(6) =520788460a(7) =3976323744a(8) =27974148068a(9) =184411212644

External references