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A324520
Number of integer partitions of n > 0 where the minimum part equals the number of parts minus the number of distinct parts.
16
0, 1, 0, 1, 2, 2, 3, 3, 7, 6, 11, 12, 15, 21, 25, 31, 43, 49, 58, 79, 89, 108, 135, 165, 190, 232, 279, 328, 387, 461, 536, 650, 743, 870, 1029, 1202, 1381, 1613, 1864, 2163, 2505, 2875, 3292, 3829, 4367, 5001, 5746, 6538, 7462, 8533, 9714, 11008, 12527, 14196
OFFSET
1,5
COMMENTS
The Heinz numbers of these integer partitions are given by A324519.
EXAMPLE
The a(2) = 1 through a(11) = 11 integer partitions:
(11) (211) (221) (222) (331) (611) (441) (811) (551)
(311) (411) (511) (3221) (711) (3322) (911)
(3211) (4211) (3222) (4222) (3332)
(3321) (5221) (4331)
(4221) (5311) (4421)
(4311) (6211) (5222)
(5211) (5411)
(6221)
(6311)
(7211)
(43211)
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], Min@@#==Length[#]-Length[Union[#]]&]], {n, 30}]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Mar 06 2019
STATUS
approved