The On-Line Encyclopedia of Integer Sequences (OEIS)

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A180988

T(n,k)=number of nXk binary matrices with rows in lexicographically nondecreasing order and columns in strictly increasing order
(history; published version)

#3 by Russ Cox at Sat Mar 31 12:35:49 EDT 2012

AUTHOR

_R. H. Hardin (rhhardin(AT)att.net) _ Sep 30 2010

Discussion

Sat Mar 31

12:35

OEIS Server: https://oeis.org/edit/global/875

#2 by N. J. A. Sloane at Thu Nov 11 07:34:06 EST 2010

LINKS

R. H. Hardin, <a href="/A180988/b180988.txt">Table of n, a(n) for n=1..287</a>

KEYWORD

nonn,tabl,new

#1 by N. J. A. Sloane at Sat Oct 02 03:00:00 EDT 2010

NAME

T(n,k)=number of nXk binary matrices with rows in lexicographically nondecreasing order and columns in strictly increasing order

DATA

2, 1, 3, 0, 4, 4, 0, 3, 10, 5, 0, 1, 21, 20, 6, 0, 0, 33, 85, 35, 7, 0, 0, 34, 330, 260, 56, 8, 0, 0, 21, 1027, 2051, 666, 84, 9, 0, 0, 7, 2429, 14610, 9646, 1506, 120, 10, 0, 0, 1, 4326, 86669, 140199, 37527, 3102, 165, 11, 0, 0, 0, 5848, 417934, 1820715, 1042746, 126889

OFFSET

1,1

COMMENTS

Table starts

..2...1.....0.......0.........0...........0.............0................0

..3...4.....3.......1.........0...........0.............0................0

..4..10....21......33........34..........21.............7................1

..5..20....85.....330......1027........2429..........4326.............5848

..6..35...260....2051.....14610.......86669........417934..........1644628

..7..56...666....9646....140199.....1820715......20114655........187187759

..8..84..1506...37527...1042746....27740695.....653629616......13274938582

..9.120..3102..126889...6452404...337921780...16343840487.....696496706166

.10.165..5940..384585..34637217..3474279349..336821069819...29455736927336

.11.220.10725.1066848.165746932.31178428721.5958448681626.1054259213026448

LINKS

R. H. Hardin, <a href="b180988.txt">Table of n, a(n) for n=1..287</a>

EXAMPLE

All solutions for 3X3

..0..0..0....0..0..0....0..0..0....0..0..1....0..0..1....0..0..1....0..0..1

..0..0..1....0..0..1....0..1..1....0..1..0....0..1..0....0..0..1....0..0..1

..0..1..0....0..1..1....1..0..1....0..1..0....0..1..1....0..1..0....0..1..1

...

..0..0..1....0..0..1....0..0..1....0..0..1....0..0..1....0..0..1....0..0..1

..0..1..1....0..1..0....0..1..0....0..1..0....0..1..0....0..1..1....0..1..1

..0..1..1....1..0..0....1..1..0....1..0..1....1..1..1....1..0..0....1..1..0

...

..0..0..1....0..0..1....0..1..1....0..1..1....0..1..1....0..1..1....0..1..1

..0..1..1....0..1..1....0..1..1....1..0..0....1..0..1....1..0..1....1..0..1

..1..0..1....1..1..1....1..0..1....1..0..1....1..1..0....1..0..1....1..1..1

KEYWORD

nonn,tabl,new

AUTHOR

R. H. Hardin (rhhardin(AT)att.net) Sep 30 2010

STATUS

approved