OFFSET
0,9
EXAMPLE
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]
MATHEMATICA
Table[Sum[Length[Select[Tuples[IntegerPartitions[#, {Length[ptn]}]&/@ptn], And@@Greater@@@#&&And@@Greater@@@Transpose[#]&]], {ptn, IntegerPartitions[n]}], {n, 30}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Jan 17 2019
STATUS
approved