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Revision History for A114736

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Showing entries 1-10 | older changes
Number of planar partitions of n where parts strictly decrease along each row and column.
(history; published version)
#23 by Andrey Zabolotskiy at Wed Jan 12 09:50:25 EST 2022
STATUS

editing

approved

#22 by Andrey Zabolotskiy at Wed Jan 12 09:50:21 EST 2022
MATHEMATICA

prs2mat[prs_]:=Table[Count[prs, {i, j}], {i, Union[First/@prs]}, {j, Union[Last/@prs]}];

multsubs[set_, k_]:=If[k==0, {{}}, Join@@Table[Prepend[#, set[[i]]]&/@multsubs[Drop[set, i-1], k-1], {i, Length[set]}]];

Table[Length[Select[multsubs[Tuples[Range[n], 2], n], And[Union[First/@#]==Range[Max@@First/@#], Union[Last/@#]==Range[Max@@Last/@#], And@@(OrderedQ[#, Greater]&/@prs2mat[#]), And@@(OrderedQ[#, Greater]&/@Transpose[prs2mat[#]])]&]], {n, 5}] (* Gus Wiseman, Nov 15 2018 *)

PROG

prs2mat[prs_]:=Table[Count[prs, {i, j}], {i, Union[First/@prs]}, {j, Union[Last/@prs]}];

multsubs[set_, k_]:=If[k==0, {{}}, Join@@Table[Prepend[#, set[[i]]]&/@multsubs[Drop[set, i-1], k-1], {i, Length[set]}]];

Table[Length[Select[multsubs[Tuples[Range[n], 2], n], And[Union[First/@#]==Range[Max@@First/@#], Union[Last/@#]==Range[Max@@Last/@#], And@@(OrderedQ[#, Greater]&/@prs2mat[#]), And@@(OrderedQ[#, Greater]&/@Transpose[prs2mat[#]])]&]], {n, 5}] (* Gus Wiseman, Nov 15 2018 *)

STATUS

approved

editing

#21 by Susanna Cuyler at Fri Nov 16 07:48:41 EST 2018
STATUS

proposed

approved

#20 by Gus Wiseman at Thu Nov 15 22:15:21 EST 2018
STATUS

editing

proposed

#19 by Gus Wiseman at Thu Nov 15 22:14:05 EST 2018
#18 by Gus Wiseman at Thu Nov 15 21:40:22 EST 2018
EXAMPLE

From Gus Wiseman, Nov 15 2018: (Start)

The a(6) = 10 plane partitions:

6 5 1 4 2 3 2 1

.

5 4 1 4 3 2 3 1

1 1 2 1 2

.

3

2

1

(End)

PROG

prs2mat[prs_]:=Table[Count[prs, {i, j}], {i, Union[First/@prs]}, {j, Union[Last/@prs]}];

multsubs[set_, k_]:=If[k==0, {{}}, Join@@Table[Prepend[#, set[[i]]]&/@multsubs[Drop[set, i-1], k-1], {i, Length[set]}]];

Table[Length[Select[multsubs[Tuples[Range[n], 2], n], And[Union[First/@#]==Range[Max@@First/@#], Union[Last/@#]==Range[Max@@Last/@#], And@@(OrderedQ[#, Greater]&/@prs2mat[#]), And@@(OrderedQ[#, Greater]&/@Transpose[prs2mat[#]])]&]], {n, 5}] (* Gus Wiseman, Nov 15 2018 *)

STATUS

approved

editing

#17 by Alois P. Heinz at Wed Sep 26 19:12:25 EDT 2018
STATUS

editing

approved

#16 by Alois P. Heinz at Wed Sep 26 19:12:22 EDT 2018
LINKS

Alois P. Heinz, <a href="/A114736/b114736.txt">Table of n, a(n) for n = 0..85</a>

#15 by Alois P. Heinz at Wed Sep 26 18:12:02 EDT 2018
KEYWORD

more,nonn,changed

EXTENSIONS

a(40)-a(44) from Alois P. Heinz, Sep 26 2018

#14 by Alois P. Heinz at Wed Sep 26 18:11:18 EDT 2018
DATA

1, 1, 1, 3, 4, 6, 10, 15, 22, 33, 49, 70, 102, 146, 205, 290, 405, 561, 779, 1071, 1463, 1999, 2714, 3667, 4946, 6641, 8880, 11848, 15753, 20870, 27586, 36354, 47766, 62621, 81878, 106785, 138975, 180449, 233778, 302270, 390027, 502256, 645603, 828330, 1060851

STATUS

approved

editing