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A227061
T(n,k) = Number of (n+k-1) X (n+k-1) binary arrays with k 1s in every row and column with rows and columns in lexicographically nondecreasing order.
4
1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 3, 5, 1, 1, 1, 5, 25, 13, 1, 1, 1, 8, 161, 272, 42, 1, 1, 1, 13, 1112, 7776, 4070, 155, 1, 1, 1, 21, 8787, 287311, 626649, 79221, 636, 1, 1, 1, 34, 76156, 13704640, 137393147, 70821384, 1906501, 2889, 1, 1, 1, 55, 728699, 809171699
OFFSET
1,9
COMMENTS
Table starts
.1...1.....1......1......1....1.....1..1.1.1
.1...1.....1......1......1....1.....1..1.1
.1...2.....3......5......8...13....21.34
.1...5....25....161...1112.8787.76156
.1..13...272...7776.287311
.1..42..4070.626649
.1.155.79221
.1.636
EXAMPLE
Some solutions for n=4 k=4
..0..0..0..1..1..1..1....0..0..0..1..1..1..1....0..0..0..1..1..1..1
..0..1..1..0..0..1..1....0..1..1..0..0..1..1....0..0..0..1..1..1..1
..0..1..1..0..1..0..1....0..1..1..0..1..0..1....0..1..1..0..0..1..1
..1..0..0..1..0..1..1....1..0..0..1..1..1..0....1..0..0..1..1..0..1
..1..0..1..1..1..0..0....1..0..1..0..0..1..1....1..1..1..0..0..1..0
..1..1..0..1..0..1..0....1..1..0..1..1..0..0....1..1..1..0..1..0..0
..1..1..1..0..1..0..0....1..1..1..1..0..0..0....1..1..1..1..0..0..0
CROSSREFS
Column 2 is A229161(n+1).
Column 3 is A229162(n+2).
Column 4 is A229163(n+3).
Column 5 is A229164(n+4).
Row 3 is A000045(n+1).
Row 4 is A181344(n+3).
Sequence in context: A290759 A306245 A275043 * A201949 A291709 A326323
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin Sep 17 2013
EXTENSIONS
More terms from Sean A. Irvine, Sep 12 2019
STATUS
approved