A089006
Number of distinct n X n (0,1) matrices after double sorting: by row, by column, by row .. until reaching a fixed point.
Original entry on oeis.org
1, 2, 7, 45, 650, 24520, 2625117, 836488618, 818230288201, 2513135860300849, 24686082394548211147, 787959836124458000837941, 82905574521614049485027140026
Offset: 0
The 7 (2 X 2)-matrices are {{0,0},{0,0}}, {{0,0},{0,1}}, {{0,0},{1,1}}, {{0,1},{0,1}}, {{0,1},{1,0}}, {{0,1},{1,1}} and {{1,1},{1,1}}.
- Adolf Mader and Otto Mutzbauer, "Double Orderings of (0,1) Matrices", Ars Combinatoria v. 61 (2001) pp 81-95.
-
baseform[li_List] := FixedPoint[Sort[Transpose[Sort[Transpose[Sort[ #1]]]]]&, li]; Table[Length@Split[Sort[baseform/@(Partition[ #, n]&/@(IntegerDigits[Range[0, -1+2^n^2], 2, n^2]))]], {n, 4}]
a(6)-a(12) found by
R. H. Hardin, May 08 2008. These terms were found using bdd's (binary decision diagrams), just setting up the logical relations between bits in a gigantic bdd expression and using that to count the satisfying states.
A184138
Number of n X 3 binary arrays with rows and columns in nondecreasing order.
Original entry on oeis.org
4, 14, 45, 130, 336, 785, 1682, 3351, 6280, 11176, 19031, 31200, 49492, 76275, 114596, 168317, 242268, 342418, 476065, 652046, 880968, 1175461, 1550454, 2023475, 2614976, 3348684, 4251979, 5356300, 6697580, 8316711, 10260040, 12579897
Offset: 1
Some solutions for 5 X 3:
..0..0..0....0..0..0....0..0..0....0..0..1....0..1..1....0..0..0....0..0..0
..0..0..1....0..0..1....0..0..0....0..1..0....0..1..1....0..1..1....0..0..1
..1..1..0....1..1..1....0..0..0....0..1..0....1..0..1....0..1..1....0..1..1
..1..1..0....1..1..1....0..0..1....0..1..1....1..0..1....0..1..1....1..1..0
..1..1..0....1..1..1....1..1..1....1..0..1....1..1..1....0..1..1....1..1..1
A184139
Number of nX4 binary arrays with rows and columns in nondecreasing order.
Original entry on oeis.org
5, 25, 130, 650, 2942, 11819, 42305, 136564, 402910, 1099694, 2805530, 6748066, 15412437, 33626131, 70430778, 142218719, 277853339, 526833235, 972034814, 1749218190, 3076360192, 5297051455, 8943742419, 14828643610, 24172697276
Offset: 1
Some solutions for 3X4
..0..0..1..1....0..0..0..0....0..1..1..1....0..0..1..1....0..0..0..1
..1..1..0..0....0..0..1..1....1..0..0..1....0..1..0..1....0..0..0..1
..1..1..1..1....1..1..1..1....1..0..1..1....1..1..1..0....0..0..0..1
A184140
Number of nX5 binary arrays with rows and columns in nondecreasing order.
Original entry on oeis.org
6, 41, 336, 2942, 24520, 183010, 1202234, 6979061, 36211867, 170079565, 731624096, 2911895183, 10815978253, 37768115174, 124748330554, 391810133592, 1175449312215, 3381493985527, 9359644588182, 25000202714062, 64609485660764
Offset: 1
Some solutions for 3X5
..0..0..1..1..1....0..1..1..1..1....0..0..1..1..1....0..0..0..0..1
..0..1..0..1..1....1..0..0..0..0....0..1..0..0..0....0..1..1..1..1
..1..1..0..0..1....1..1..1..1..1....1..1..1..1..1....1..0..0..0..0
A184141
Number of nX6 binary arrays with rows and columns in nondecreasing order.
Original entry on oeis.org
7, 63, 785, 11819, 183010, 2625117, 33345183, 371484319, 3651371519, 32017940222, 253426591764, 1830279313811, 12175210709509, 75202293506213, 434279600673295, 2358572224659659, 12108001563352798, 59013152727127932
Offset: 1
Some solutions for 3X6
..0..0..0..1..1..1....0..0..0..0..1..1....0..0..0..1..1..1....0..1..1..1..1..1
..0..0..1..0..0..1....0..0..0..1..0..1....0..0..1..0..0..1....1..0..1..1..1..1
..0..1..1..0..1..1....0..0..0..1..1..1....1..1..1..0..0..1....1..1..0..0..0..0
A184142
Number of nX7 binary arrays with rows and columns in nondecreasing order.
Original entry on oeis.org
8, 92, 1682, 42305, 1202234, 33345183, 836488618, 18470742266, 358194085968, 6148026957098, 94402700488339, 1310734458313359, 16616390002366515, 193963806947349704, 2100034143080950846, 21221195503865955621
Offset: 1
Some solutions for 3X7
..0..0..0..0..0..0..1....0..0..0..0..0..1..1....0..0..1..1..1..1..1
..0..1..1..1..1..1..1....0..0..0..0..0..1..1....0..1..0..0..0..1..1
..1..0..0..0..1..1..1....0..1..1..1..1..0..0....1..1..1..1..1..0..0
A184143
Number of nX8 binary arrays with rows and columns in nondecreasing order.
Original entry on oeis.org
9, 129, 3351, 136564, 6979061, 371484319, 18470742266, 818230288201, 31887670171373, 1096628939510047, 33575397457792227, 924491977646105742, 23115171441961340021, 529351592443419400759, 11186675629728308277811
Offset: 1
Some solutions for 3X8
..0..1..1..1..1..1..1..1....0..0..0..0..0..1..1..1....0..0..1..1..1..1..1..1
..1..0..0..1..1..1..1..1....0..0..0..1..1..0..0..0....0..1..0..0..0..1..1..1
..1..0..1..0..0..0..1..1....0..0..0..1..1..0..1..1....1..0..0..1..1..0..0..1
Showing 1-7 of 7 results.
Comments