A195768 T(n,k)=Number of triangular nXnXn 0..k arrays with all row sums equal to the length of the row and all diagonal sums equal to the length of the respective diagonal

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 3, 15, 1, 1, 1, 1, 3, 18, 135, 1, 1, 1, 1, 3, 18, 228, 2889, 1, 1, 1, 1, 3, 18, 228, 8472, 146559, 1, 1, 1, 1, 3, 18, 228, 8904, 898125, 17742675, 1, 1, 1, 1, 3, 18, 228, 8904, 1037343, 276763188, 5342155407, 1, 1, 1, 1, 3

Offset

1,14

Comments

Table starts

.1........1.........1.........1.......1....1...1..1.1.1.1.1

.1........1.........1.........1.......1....1...1..1.1.1.1

.1........1.........1.........1.......1....1...1..1.1.1

.1........3.........3.........3.......3....3...3..3.3

.1.......15........18........18......18...18..18.18

.1......135.......228.......228.....228..228.228

.1.....2889......8472......8904....8904.8904

.1...146559....898125...1037343.1039761

.1.17742675.276763188.374504433

Links

R. H. Hardin, Table of n, a(n) for n = 1..75

Example

Some solutions for n=8 k=6
.........1................1................1................1
........0.2..............0.2..............0.2..............0.2
.......2.0.1............2.0.1............0.1.2............2.0.1
......1.0.0.3..........1.0.2.1..........1.1.2.0..........1.1.1.1
.....1.2.1.1.0........1.0.2.2.0........0.2.1.1.1........1.0.0.2.2
....0.1.1.0.4.0......2.2.1.1.0.0......3.1.1.0.1.0......1.1.2.0.2.0
...2.2.2.1.0.0.0....0.1.0.0.1.3.2....2.0.0.1.2.1.1....1.2.2.2.0.0.0
..1.0.1.0.0.3.2.1..1.2.0.1.3.0.0.1..1.0.0.3.0.2.1.1..1.1.0.0.0.3.2.1

Crossrefs

Sequence in context: A062278 A260638 A268523 * A016465 A122947 A367990

Adjacent sequences: A195765 A195766 A195767 * A195769 A195770 A195771

Keyword

nonn,tabl

Author

R. H. Hardin Sep 23 2011

Status

approved