Number of n X 1 0..3 arrays with values 0..3 introduced in row major order and each element equal to one or two horizontal and vertical neighbors.
A199142
Number of n X 1 0..3 arrays with values 0..3 introduced in row major order and each element equal to one or two horizontal and vertical neighbors.
Terms
- a(0) =0a(1) =1a(2) =1a(3) =2a(4) =3a(5) =6a(6) =11a(7) =23a(8) =47a(9) =102a(10) =221a(11) =492a(12) =1099a(13) =2485a(14) =5637a(15) =12858a(16) =29391a(17) =67354a(18) =154539a(19) =355003a(20) =816035a(21) =1876862a(22) =4318201a(23) =9937840a(24) =22874731a(25) =52659593a(26) =121237417a(27) =279141170a(28) =642732027a(29) =1479959118
External references
- oeis: A199142