Number of nX5 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,2,1,1,1 for x=0,1,2,3,4.

A197542

Number of nX5 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,2,1,1,1 for x=0,1,2,3,4.

Terms

    a(0) =4a(1) =28a(2) =61a(3) =206a(4) =494a(5) =2095a(6) =6279a(7) =21530a(8) =69977a(9) =248366a(10) =813400a(11) =2838023a(12) =9457181a(13) =32284759a(14) =108523371a(15) =370702868a(16) =1251432293a(17) =4258479323a(18) =14389442735a(19) =48816423022a(20) =165305055080a(21) =561221682936

External references