Number of n X 3 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,3,2,1,2 for x=0,1,2,3,4.
A197237
Number of n X 3 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 4,3,2,1,2 for x=0,1,2,3,4.
Terms
- a(0) =1a(1) =5a(2) =15a(3) =46a(4) =156a(5) =507a(6) =1637a(7) =5338a(8) =17401a(9) =56648a(10) =184384a(11) =600287a(12) =1954546a(13) =6363740a(14) =20718710a(15) =67455328a(16) =219621081a(17) =715042212a(18) =2328028685a(19) =7579574414a(20) =24677521267a(21) =80344901649a(22) =261586345777a(23) =851670870944
External references
- oeis: A197237