Number of length-7 0..n arrays with no adjacent pair x,x+1 repeated.

Terms

a(0) =64a(1) =1710a(2) =14596a(3) =73348a(4) =269472a(5) =803434a(6) =2061940a(7) =4725456a(8) =9911008a(9) =19355302a(10) =35643204a(11) =62486620a(12) =105058816a(13) =170389218a(14) =267823732a(15) =409555624a(16) =611232000a(17) =892640926a(18) =1278484228a(19) =1799241012a(20) =2492126944a(21) =3402154330a(22) =4583298036