Number of (n+1)X4 0..3 arrays with every 2X2 subblock trace equal to exactly one or two horizontal and vertical neighbor 2X2 subblock traces.
A186917
Number of (n+1)X4 0..3 arrays with every 2X2 subblock trace equal to exactly one or two horizontal and vertical neighbor 2X2 subblock traces.
Terms
- a(0) =2176a(1) =253312a(2) =7946432a(3) =394724320a(4) =15491352288a(5) =686342587904
External references
- oeis: A186917