1/6 the number of (n+2)X5 0..2 arrays with each 3X3 subblock containing one of one value, four of another, and four of the last.
A184471
1/6 the number of (n+2)X5 0..2 arrays with each 3X3 subblock containing one of one value, four of another, and four of the last.
Terms
- a(0) =3705a(1) =7085a(2) =14119a(3) =30681a(4) =86575a(5) =249953a(6) =747735a(7) =2652785a(8) =9085231a(9) =30632409a(10) =117322423a(11) =424882145a(12) =1490248815a(13) =5857018745a(14) =21643873159a(15) =77054809761a(16) =305865631855
External references
- oeis: A184471