Number of 2 X n 0..3 arrays with antidiagonals unimodal and rows and diagonals nondecreasing.

Terms

a(0) =16a(1) =85a(2) =295a(3) =805a(4) =1876a(5) =3906a(6) =7470a(7) =13365a(8) =22660a(9) =36751a(10) =57421a(11) =86905a(12) =127960a(13) =183940a(14) =258876a(15) =357561a(16) =485640a(17) =649705a(18) =857395a(19) =1117501a(20) =1440076a(21) =1836550a(22) =2319850a(23) =2904525a(24) =3606876a(25) =4445091a(26) =5439385a(27) =6612145a(28) =7988080a(29) =9594376