Number of permutations of 0..floor((n*3-2)/2) on odd squares of an n X 3 array such that each row and column of odd squares is increasing.
A215294
Number of permutations of 0..floor((n*3-2)/2) on odd squares of an n X 3 array such that each row and column of odd squares is increasing.
Terms
- a(0) =1a(1) =3a(2) =6a(3) =30a(4) =70a(5) =420a(6) =1050a(7) =6930a(8) =18018a(9) =126126a(10) =336336a(11) =2450448a(12) =6651216a(13) =49884120a(14) =137181330a(15) =1051723530a(16) =2921454250a(17) =22787343150a(18) =63804560820a(19) =504636071940
External references
- oeis: A215294