Number of n X 4 nonnegative integer arrays with upper left 0 and lower right its king-move distance away minus 3 and every value increasing by 0 or 1 with every step right, diagonally se or down.

A253007

Number of n X 4 nonnegative integer arrays with upper left 0 and lower right its king-move distance away minus 3 and every value increasing by 0 or 1 with every step right, diagonally se or down.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =124a(5) =3423a(6) =33533a(7) =158877a(8) =490403a(9) =1156178a(10) =2286874a(11) =4013538a(12) =6467242a(13) =9779058a(14) =14080058a(15) =19501314a(16) =26173898a(17) =34228882a(18) =43797338a(19) =55010338a(20) =67998954a(21) =82894258a(22) =99827322a(23) =118929218a(24) =140331018a(25) =164163794a(26) =190558618a(27) =219646562

External references