Number of n X 2 0..2 arrays with rows, antidiagonals and columns unimodal.

Terms

a(0) =9a(1) =81a(2) =484a(3) =2116a(4) =7396a(5) =21904a(6) =57121a(7) =134689a(8) =292681a(9) =594441a(10) =1140624a(11) =2085136a(12) =3655744a(13) =6180196a(14) =10118761a(15) =16104169a(16) =24990001a(17) =37908649a(18) =56340036a(19) =82192356a(20) =117896164a(21) =166513216a(22) =231861529a(23) =318658201a(24) =432681601a(25) =580954609a(26) =771950656