Number of nX2 0..3 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order.

A278721

Number of nX2 0..3 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order.

Terms

    a(0) =10a(1) =60a(2) =275a(3) =1050a(4) =3492a(5) =10401a(6) =28288a(7) =71266a(8) =168155a(9) =374868a(10) =795158a(11) =1614184a(12) =3151188a(13) =5939970a(14) =10848924a(15) =19256291a(16) =33301148a(17) =56236656a(18) =92919425a(19) =150477730a(20) =239211960a(21) =373793355a(22) =574842060a(23) =870983100a(24) =1301499381a(25) =1919724600

External references