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A114640
Number of partitions of n such that the set of parts and the set of multiplicities of parts are equal.
29
1, 1, 0, 0, 2, 1, 1, 0, 1, 1, 3, 2, 3, 3, 5, 0, 4, 5, 2, 3, 8, 6, 5, 10, 9, 9, 16, 14, 12, 16, 17, 10, 17, 15, 16, 19, 35, 17, 34, 37, 40, 31, 54, 36, 60, 61, 58, 63, 88, 58, 88, 87, 91, 84, 115, 93, 116, 108, 115, 130, 190, 143, 165, 214, 219, 200, 255, 240
OFFSET
0,5
COMMENTS
The Heinz numbers of these partitions are given by A109297. - Gus Wiseman, Apr 02 2019
EXAMPLE
From Gus Wiseman, Apr 02 2019: (Start)
The initial terms count the following integer partitions:
0: ()
1: (1)
4: (22)
4: (211)
5: (221)
6: (3111)
8: (41111)
9: (333)
10: (511111)
10: (3331)
10: (322111)
11: (332111)
11: (322211)
12: (6111111)
12: (4221111)
12: (33222)
13: (33322)
13: (333211)
13: (332221)
14: (71111111)
14: (52211111)
14: (4421111)
14: (4222211)
14: (333221)
(End)
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], Union[#]==Union[Length/@Split[#]]&]], {n, 0, 30}] (* Gus Wiseman, Apr 02 2019 *)
KEYWORD
nonn
AUTHOR
Vladeta Jovovic, Feb 18 2006
EXTENSIONS
More terms from Alois P. Heinz, Aug 09 2016
STATUS
approved