Number of n X 2 0..2 arrays x(i,j) with each element horizontally or vertically next to at least one element with value 2-x(i,j).

A229841

Number of n X 2 0..2 arrays x(i,j) with each element horizontally or vertically next to at least one element with value 2-x(i,j).

Terms

    a(0) =3a(1) =15a(2) =81a(3) =423a(4) =2247a(5) =11925a(6) =63291a(7) =335943a(8) =1783137a(9) =9464655a(10) =50237151a(11) =266652213a(12) =1415355027a(13) =7512519135a(14) =39875467761a(15) =211653760983

External references