Number of 3 X n 0..1 arrays with rows and antidiagonals unimodal and columns nondecreasing.

Terms

a(0) =4a(1) =16a(2) =49a(3) =124a(4) =275a(5) =554a(6) =1037a(7) =1831a(8) =3082a(9) =4984a(10) =7789a(11) =11818a(12) =17473a(13) =25250a(14) =35753a(15) =49709a(16) =67984a(17) =91600a(18) =121753a(19) =159832a(20) =207439a(21) =266410a(22) =338837a(23) =427091a(24) =533846a(25) =662104a(26) =815221a(27) =996934a(28) =1211389a(29) =1463170