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A306320
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Number of square plane partitions of n with distinct row sums and distinct column sums.
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1
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1, 1, 1, 1, 1, 2, 2, 5, 5, 10, 11, 18, 21, 31, 37, 56, 70, 97, 134, 180, 247, 343, 462, 623, 850, 1128, 1509, 2004, 2649, 3467, 4590, 5958, 7814, 10161, 13287, 17208, 22495, 29129, 37997, 49229, 64098, 82940, 107868, 139390, 180737, 233214, 301527, 388018, 500058
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OFFSET
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0,6
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LINKS
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EXAMPLE
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The a(12) = 21 square plane partitions with distinct row sums and distinct column sums:
[twelve]
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[64][73][82][91][54][63][72][81][44][53][53][62][62][71][43][43][52][52][61]
[11][11][11][11][21][21][21][21][31][22][31][22][31][31][32][41][32][41][41]
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[221]
[211]
[111]
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MATHEMATICA
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Table[Sum[Length[Select[Union[Reverse/@Sort/@Tuples[IntegerPartitions[#, {Length[ptn]}]&/@ptn]], UnsameQ@@Total/@#&&UnsameQ@@Total/@If[#=={}, {}, Transpose[#]]&&And@@OrderedQ/@Reverse/@If[#=={}, {}, Transpose[#]]&]], {ptn, IntegerPartitions[n]}], {n, 0, 20}]
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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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