Number of n X 2 0..2 arrays with some element plus some horizontally or vertically adjacent neighbor totalling two no more than once.
A268622
Number of n X 2 0..2 arrays with some element plus some horizontally or vertically adjacent neighbor totalling two no more than once.
Terms
- a(0) =9a(1) =42a(2) =174a(3) =666a(4) =2430a(5) =8586a(6) =29646a(7) =100602a(8) =336798a(9) =1115370a(10) =3661038a(11) =11927898a(12) =38618046a(13) =124357194a(14) =398580750a(15) =1272269754a(16) =4046391774a(17) =12827922858a(18) =40550011182a(19) =127848761370a(20) =402142467582
External references
- oeis: A268622