Number of n X 4 nonnegative integer arrays with upper left 0 and lower right n+4-6 and value increasing by 0 or 1 with every step right or down.

A252926

Number of n X 4 nonnegative integer arrays with upper left 0 and lower right n+4-6 and value increasing by 0 or 1 with every step right or down.

Terms

    a(0) =0a(1) =1a(2) =33a(3) =615a(4) =6997a(5) =53950a(6) =315198a(7) =1499394a(8) =6083808a(9) =21733215a(10) =69921908a(11) =206052448a(12) =563440284a(13) =1444285973a(14) =3499040581a(15) =8065603025a(16) =17787652381a(17) =37705694442a(18) =77126966988a(19) =152747362302a(20) =293741640632a(21) =549886035657

External references