A202864 T(n,k) = Number of n X n 0..k arrays with row and column sums one greater than the previous row and column.

2, 3, 2, 4, 6, 2, 5, 12, 42, 2, 6, 20, 228, 1346, 2, 7, 30, 776, 41852, 223456, 2, 8, 42, 2046, 491892, 80524892, 202999208, 2, 9, 56, 4578, 3436102, 5393851108, 1720483641156, 1049899768685, 2, 10, 72, 9128, 17232446, 147978735402, 1081958661341802

Offset

1,1

Links

Table of n, a(n) for n=1..42.

Example

Table starts
.2.............3.............4................5............6........7....8..9
.2.............6............12...............20...........30.......42...56.72
.2............42...........228..............776.........2046.....4578.9128
.2..........1346.........41852...........491892......3436102.17232446
.2........223456......80524892.......5393851108.147978735402
.2.....202999208.1720483641156.1081958661341802
.2.1049899768685
.2
Some solutions for n=4 k=3
..0..1..1..3....1..0..2..1....1..1..0..2....2..1..0..1....1..0..1..0
..1..2..1..2....0..1..1..3....3..0..1..1....1..1..0..3....0..1..1..1
..2..0..2..3....3..3..0..0....0..2..3..1....0..2..3..1....0..0..1..3
..2..3..3..0....0..1..3..3....0..2..2..3....1..1..3..2....1..2..1..1

Crossrefs

Row 2 is A002378.

Sequence in context: A194998 A215190 A214943 * A328880 A291290 A006047

Adjacent sequences: A202861 A202862 A202863 * A202865 A202866 A202867

Keyword

nonn,tabl,more

Author

R. H. Hardin, Dec 25 2011

Status

approved