Number of nX6 0..1 arrays with rows and columns unimodal.

Terms

a(0) =22a(1) =484a(2) =6504a(3) =57238a(4) =367216a(5) =1856100a(6) =7795951a(7) =28248007a(8) =90732638a(9) =263650284a(10) =703980614a(11) =1748547620a(12) =4079672416a(13) =9012596316a(14) =18975151965a(15) =38281575869a(16) =74344179766a(17) =139521245076a(18) =253869738212a(19) =449160402594a(20) =774624001120