A222836 Number of nX6 0..3 arrays with no element equal to another at a city block distance of exactly two, and new values 0..3 introduced in row major order

55, 1536, 1944, 4056, 9600, 24576, 55296, 124416, 279936, 645504, 1476096, 3393024, 7742976, 17750400, 40560000, 92952576, 212557824, 486864384, 1113680256, 2550116736, 5834651136, 13357979136, 30567200256, 69973632384, 160134620544

Offset

1,1

Comments

Column 6 of A222838

Links

R. H. Hardin, Table of n, a(n) for n = 1..112

Formula

Empirical: a(n) = 2*a(n-1) +2*a(n-2) -4*a(n-3) +4*a(n-4) -4*a(n-5) +2*a(n-6) -6*a(n-7) +a(n-10) for n>14

Example

Some solutions for n=4
..0..1..2..2..3..0....0..1..1..2..0..3....0..1..2..2..1..3....0..1..2..0..3..1
..0..3..3..0..1..1....0..2..3..3..1..2....0..1..3..3..0..0....2..1..3..0..2..2
..2..2..1..0..2..3....1..2..0..0..1..2....3..2..0..1..2..2....2..0..3..1..1..3
..3..0..1..3..2..0....3..3..1..2..3..3....3..2..0..1..3..3....3..0..2..2..0..0

Crossrefs

Sequence in context: A017771 A322502 A271796 * A017718 A173113 A166844

Adjacent sequences: A222833 A222834 A222835 * A222837 A222838 A222839

Keyword

nonn

Author

R. H. Hardin Mar 06 2013

Status

approved