Number of n X 2 0..2 arrays with every nonzero element less than or equal to at least two horizontal and vertical neighbors.
A203454
Number of n X 2 0..2 arrays with every nonzero element less than or equal to at least two horizontal and vertical neighbors.
Terms
- a(0) =1a(1) =3a(2) =9a(3) =22a(4) =63a(5) =209a(6) =686a(7) =2228a(8) =7365a(9) =24619a(10) =82433a(11) =276500a(12) =929936a(13) =3133114a(14) =10566260a(15) =35661359a(16) =120433051a(17) =406897030a(18) =1375168827a(19) =4648638160a(20) =15716950105a(21) =53145110566a(22) =179719928744a(23) =607794550141
External references
- oeis: A203454