Sum of the perimeters of the free polyominoes with n cells.

A380287

Sum of the perimeters of the free polyominoes with n cells.

Terms

    a(0) =4a(1) =6a(2) =16a(3) =48a(4) =142a(5) =472a(6) =1670a(7) =6364a(8) =24604a(9) =97668a(10) =390070a(11) =1570560a(12) =6334644a(13) =25617062a(14) =103669288a(15) =419930444a(16) =1701635046a(17) =6898183050

External references