Number of 0..n arrays of length 8 with 0 never adjacent to n.

Terms

a(0) =2a(1) =1393a(2) =28642a(3) =231521a(4) =1168786a(5) =4414417a(6) =13667858a(7) =36590017a(8) =87627106a(9) =192124721a(10) =392074882a(11) =753879073a(12) =1378550642a(13) =2414820241a(14) =4075648306a(15) =6658688897a(16) =10571289538a(17) =16360652017a(18) =24749819426a(19) =36680195041a(20) =53361338962