Number of 2Xn 0..3 arrays with exactly floor(2Xn/2) elements unequal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.
A222795
Number of 2Xn 0..3 arrays with exactly floor(2Xn/2) elements unequal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..3 order.
Terms
- a(0) =0a(1) =3a(2) =4a(3) =18a(4) =62a(5) =302a(6) =1246a(7) =6094a(8) =26914a(9) =134498a(10) =609026a(11) =3063602a(12) =14101834a(13) =70953566a(14) =330924894a(15) =1660510388a(16) =7832513154a(17) =39166394428a(18) =186507266186a(19) =929635136724
External references
- oeis: A222795