T(n,k) = number of nXk 0..3 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor.

A203101

T(n,k) = number of nXk 0..3 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor.

Terms

    a(0) =1a(1) =4a(2) =4a(3) =16a(4) =84a(5) =16a(6) =50a(7) =1080a(8) =1080a(9) =50a(10) =144a(11) =12260a(12) =48552a(13) =12260a(14) =144a(15) =422a(16) =143510a(17) =2029744a(18) =2029744a(19) =143510a(20) =422a(21) =1268a(22) =1705124a(23) =87531478a(24) =308642476a(25) =87531478a(26) =1705124a(27) =1268a(28) =3823a(29) =20174774

External references