Number of n X 2 0..2 arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two not more than once.
A268803
Number of n X 2 0..2 arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two not more than once.
Terms
- a(0) =9a(1) =34a(2) =104a(3) =290a(4) =772a(5) =1972a(6) =4914a(7) =12010a(8) =28922a(9) =68836a(10) =162274a(11) =379524a(12) =881712a(13) =2036734a(14) =4681646a(15) =10714994a(16) =24430816a(17) =55516546a(18) =125777028a(19) =284188780a(20) =640549034a(21) =1440572818a(22) =3233256010a(23) =7243375068a(24) =16199546178a(25) =36172883716
External references
- oeis: A268803