Number of n X 3 0..3 arrays x(i,j) with each element horizontally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero.
A231103
Number of n X 3 0..3 arrays x(i,j) with each element horizontally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero.
Terms
- a(0) =0a(1) =2a(2) =8a(3) =42a(4) =208a(5) =1042a(6) =5208a(7) =26042a(8) =130208a(9) =651042a(10) =3255208a(11) =16276042a(12) =81380208a(13) =406901042a(14) =2034505208a(15) =10172526042a(16) =50862630208a(17) =254313151042
External references
- oeis: A231103