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A324572
Number of integer partitions of n whose multiplicities (where if x < y the multiplicity of x is counted prior to the multiplicity of y) are equal to the distinct parts in decreasing order.
21
1, 1, 0, 0, 2, 0, 1, 0, 1, 1, 2, 0, 3, 0, 2, 0, 4, 1, 2, 1, 4, 1, 3, 1, 5, 3, 5, 1, 6, 2, 6, 1, 7, 2, 7, 2, 11, 4, 8, 3, 11, 5, 10, 4, 13, 5, 11, 5, 16, 8, 14, 5, 19, 8, 18, 6, 22, 8, 22, 7, 26, 10, 25, 8, 33, 12, 29, 11, 36, 13, 34, 12, 40, 16, 41, 14, 47, 17, 45, 16, 55
OFFSET
0,5
COMMENTS
These are a kind of self-describing partitions (cf. A001462, A304679).
The Heinz numbers of these partitions are given by A324571.
The case where the distinct parts are taken in increasing order is counted by A033461, with Heinz numbers given by A109298.
EXAMPLE
The first 19 terms count the following integer partitions:
1: (1)
4: (22)
4: (211)
6: (3111)
8: (41111)
9: (333)
10: (511111)
10: (322111)
12: (6111111)
12: (4221111)
12: (33222)
14: (71111111)
14: (52211111)
16: (811111111)
16: (622111111)
16: (4444)
16: (442222)
17: (43331111)
18: (9111111111)
18: (7221111111)
19: (533311111)
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], Union[#]==Length/@Split[#]&]], {n, 0, 30}]
CROSSREFS
Sequences related to self-description: A000002, A001462, A079000, A079254, A276625, A304360.
Sequence in context: A292342 A091991 A108234 * A153148 A378437 A091830
KEYWORD
nonn
AUTHOR
Gus Wiseman, Mar 08 2019
EXTENSIONS
More terms from Alois P. Heinz, Mar 08 2019
STATUS
approved