Number of antichains (or order ideals) in the poset 3*3*3*n or size of the distributive lattice J(3*3*3*n).

A056937

Number of antichains (or order ideals) in the poset 3*3*3*n or size of the distributive lattice J(3*3*3*n).

Terms

    a(0) =1a(1) =980a(2) =211250a(3) =17792748a(4) =781429368a(5) =21238316210a(6) =398925639186

External references