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