A198528 T(n,k) is the number of n X k 0..4 arrays with values 0..4 introduced in row major order and each element equal to no more than two horizontal and vertical neighbors.

1, 2, 2, 5, 15, 5, 15, 193, 193, 15, 52, 3660, 16714, 3660, 52, 202, 81844, 1877316, 1877316, 81844, 202, 855, 1948672, 222590953, 1084539825, 222590953, 1948672, 855, 3845, 47436498, 26670041125, 634586561196, 634586561196, 26670041125

Offset

1,2

Links

R. H. Hardin, Table of n, a(n) for n = 1..84

Example

Table starts:
.....1............2...................5......................15
.....2...........15.................193....................3660
.....5..........193...............16714.................1877316
....15.........3660.............1877316..............1084539825
....52........81844...........222590953............634586561196
...202......1948672.........26670041125.........371815743708461
...855.....47436498.......3201911378187......217885196778717007
..3845...1163606279.....384557171168810...127683385189755792564
.18002..28617909415...46189600128813487.74824145653256981522691
.86472.704465305625.5547962760669962158
Some solutions for n=6 and k=4:
..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
..0..1..1..0....0..1..1..0....0..1..1..0....0..1..1..0....0..1..1..0
..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0
..2..2..1..2....2..2..1..2....2..2..1..2....2..2..1..2....2..2..1..2
..2..2..3..2....0..3..1..2....3..0..0..3....2..0..1..0....0..3..4..4
..1..4..0..4....3..2..4..4....3..1..4..3....1..3..0..0....3..3..0..4

Crossrefs

Main diagonal is A198521.

Columns 1..7 are A056272, A198522, A198523, A198524, A198525, A198526, A198527.

Cf. A199655, A200801.

Sequence in context: A200801 A241119 A208408 * A208466 A098888 A089848

Adjacent sequences: A198525 A198526 A198527 * A198529 A198530 A198531

Keyword

nonn,tabl

Author

R. H. Hardin, Oct 26 2011

Status

approved