A208408 T(n,k) is the number of n X k 0..3 arrays with new values 0..3 introduced in row major order and no element equal to more than two of its immediate leftward or upward or right-upward antidiagonal neighbors.

1, 2, 2, 5, 15, 5, 15, 182, 187, 15, 51, 2698, 10682, 2795, 51, 187, 41914, 658450, 667478, 43947, 187, 715, 658450, 40883360, 163422914, 42012698, 700075, 715, 2795, 10370330, 2540446156, 40039156736, 40595679634, 2646531062, 11188907, 2795

Offset

1,2

Links

R. H. Hardin, Table of n, a(n) for n = 1..198

Example

Table starts:
....1.........2..............5.................15......................51
....2........15............182...............2698...................41914
....5.......187..........10682.............658450................40883360
...15......2795.........667478..........163422914.............40039156736
...51.....43947.......42012698........40595679634..........39216100214432
..187....700075.....2646531062.....10084768380770.......38410047476679936
..715..11188907...166729574522...2505261257850802....37620564383817645696
.2795.178973355.10503950018198.622357842865595522.36847308431734650845696
...
Some solutions for n=4 and k=3:
..0..0..0....0..0..1....0..1..0....0..0..0....0..1..0....0..0..0....0..1..1
..0..1..0....0..0..0....0..2..2....0..1..1....0..2..3....0..1..2....0..0..0
..1..2..1....0..1..1....1..2..1....2..0..2....3..0..0....2..1..1....0..1..1
..0..1..3....1..2..3....1..3..2....2..1..0....2..1..3....0..1..1....0..2..1

Crossrefs

Row 1 and column 1 are A007581(n-1).

Columns 2..7 are A208402, A208403, A208404, A208405, A208406, A208407.

Rows 2..7 are A208409, A208410, A208411, A208412, A208413, A208414.

Main diagonal is A208401.

Sequence in context: A208001 A200801 A241119 * A198528 A208466 A098888

Adjacent sequences: A208405 A208406 A208407 * A208409 A208410 A208411

Keyword

nonn,tabl

Author

R. H. Hardin, Feb 26 2012

Status

approved