Number of nX3 arrays containing 3 indistinguishable copies of 1..n with lexicographical ordering of rows strictly increasing and columns strictly decreasing.
A180841
Number of nX3 arrays containing 3 indistinguishable copies of 1..n with lexicographical ordering of rows strictly increasing and columns strictly decreasing.
Terms
- a(0) =1a(1) =1a(2) =19a(3) =596a(4) =37423a(5) =3746117a(6) =545626043a(7) =109162526742
External references
- oeis: A180841