A217510 T(n,k) is the number of triangular n X n X n arrays of occupancy after each element either stays or moves to some neighbor and with no occupancy greater than k.

1, 1, 1, 1, 7, 1, 1, 10, 138, 1, 1, 10, 306, 8353, 1, 1, 10, 342, 34489, 1563486, 1, 1, 10, 351, 44530, 14162520, 896267399, 1, 1, 10, 351, 47356, 22155653, 21101953059, 1563576619949, 1, 1, 10, 351, 47518, 24754099, 42007776880, 113688398105827

Offset

1,5

Links

Table of n, a(n) for n=1..43.

Example

Table starts:
.1.............1...............1...........1........1.....1...1..1.1
.1.............7..............10..........10.......10....10..10.10
.1...........138.............306.........342......351...351.351
.1..........8353...........34489.......44530....47356.47518
.1.......1563486........14162520....22155653.24754099
.1.....896267399.....21101953059.42007776880
.1.1563576619949.113688398105827
...
Some solutions for n=4 and k=4:
.....0........2........3........0........0........0........2........2
....1.1......1.1......0.0......0.3......2.0......1.1......0.0......0.0
...1.0.2....2.1.0....1.1.2....3.2.0....0.0.1....2.1.3....0.0.1....0.4.0
..2.0.0.3..1.0.0.2..3.0.0.0..0.1.0.1..1.3.1.2..0.1.1.0..3.0.4.0..1.0.2.1

Crossrefs

Sequence in context: A050179 A358450 A183352 * A273506 A364093 A287326

Adjacent sequences: A217507 A217508 A217509 * A217511 A217512 A217513

Keyword

nonn,tabl

Author

R. H. Hardin, Oct 05 2012

Status

approved