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A325039
Number of integer partitions of n with the same product of parts as their conjugate.
20
1, 1, 0, 1, 1, 1, 1, 1, 6, 2, 2, 4, 3, 5, 7, 6, 5, 7, 9, 10, 11, 18, 16, 19, 19, 16, 20, 20, 28, 39, 28, 40, 53, 45, 52, 59, 71, 61, 73, 97, 102, 95, 112, 131, 137, 148, 140, 166, 199, 181, 238, 251, 255, 289, 339, 344, 381, 398, 422, 464, 541, 555, 628, 677, 732
OFFSET
0,9
COMMENTS
For example, the partition (6,4,1) with product 24 has conjugate (3,2,2,2,1,1) with product also 24.
The Heinz numbers of these partitions are given by A325040.
EXAMPLE
The a(8) = 6 through a(15) = 6 integer partitions:
(44) (333) (4321) (641) (4422) (4432) (6431)
(332) (51111) (52111) (4331) (53211) (6421) (8411)
(431) (322211) (621111) (53311) (54221)
(2222) (611111) (432211) (433211)
(3221) (7111111) (632111)
(4211) (7211111)
(42221111)
MATHEMATICA
conj[y_]:=If[Length[y]==0, y, Table[Length[Select[y, #>=k&]], {k, 1, Max[y]}]];
Table[Length[Select[IntegerPartitions[n], Times@@#==Times@@conj[#]&]], {n, 0, 30}]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Mar 25 2019
EXTENSIONS
More terms from Jinyuan Wang, Jun 27 2020
STATUS
approved