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A323530
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Number of square plane partitions of n with strictly decreasing rows and columns.
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3
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1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 4, 5, 8, 10, 15, 18, 25, 30, 39, 46, 58, 67, 82, 94, 112, 127, 149, 168, 194, 218, 251, 282, 324, 368, 425, 489, 573, 670, 797, 952, 1148, 1392, 1703, 2086, 2568, 3168, 3908, 4823, 5947, 7318, 8986, 11012, 13443, 16371, 19866
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OFFSET
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0,9
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LINKS
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EXAMPLE
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The a(12) = 8 plane partitions:
[12]
.
[5 4] [6 3] [7 2] [5 3] [6 2] [4 3] [5 2]
[2 1] [2 1] [2 1] [3 1] [3 1] [3 2] [4 1]
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MATHEMATICA
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Table[Sum[Length[Select[Tuples[IntegerPartitions[#, {Length[ptn]}]&/@ptn], And@@Greater@@@#&&And@@Greater@@@Transpose[#]&]], {ptn, IntegerPartitions[n]}], {n, 30}]
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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