A223784 Number of n X 3 0..2 arrays with rows, diagonals and antidiagonals unimodal.

22, 484, 8635, 151580, 2703137, 48302789, 862007289, 15379566078, 274427327200, 4896915028511, 87380287912506, 1559204462831053, 27822300189794631, 496458709513621497, 8858765510668046944, 158075026701646689756

Offset

1,1

Comments

Column 3 of A223789.

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 18*a(n-1) -24*a(n-2) +364*a(n-3) +605*a(n-4) -5879*a(n-5) -3267*a(n-6) -28514*a(n-7) -68422*a(n-8) +215872*a(n-9) +381625*a(n-10) +110428*a(n-11) +62650*a(n-12) -42873*a(n-13) -108576*a(n-14) -28080*a(n-15).

Example

Some solutions for n=3
..0..1..1....0..2..2....0..2..1....0..1..2....0..2..0....0..0..1....0..2..2
..1..1..0....1..0..0....2..2..1....0..1..1....0..2..0....2..1..0....2..2..1
..1..1..0....0..2..1....2..2..1....1..1..1....0..0..1....2..2..0....0..0..1

Crossrefs

Cf. A223789.

Sequence in context: A223826 A223618 A223678 * A223970 A171296 A009966

Adjacent sequences: A223781 A223782 A223783 * A223785 A223786 A223787

Keyword

nonn

Author

R. H. Hardin, Mar 27 2013

Status

approved