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A362048
Number of integer partitions of n such that (length) <= 2*(median).
2
1, 2, 2, 3, 4, 6, 8, 12, 15, 20, 25, 33, 41, 53, 66, 85, 105, 134, 164, 205, 250, 308, 373, 456, 549, 666, 799, 963, 1152, 1382, 1645, 1965, 2330, 2767, 3269, 3865, 4546, 5353, 6274, 7357, 8596, 10046, 11700, 13632, 15834, 18394, 21312, 24690, 28534, 32974
OFFSET
1,2
COMMENTS
The median of a multiset is either the middle part (for odd length), or the average of the two middle parts (for even length).
EXAMPLE
The a(1) = 1 through a(9) = 15 partitions:
(1) (2) (3) (4) (5) (6) (7) (8) (9)
(11) (21) (22) (32) (33) (43) (44) (54)
(31) (41) (42) (52) (53) (63)
(221) (51) (61) (62) (72)
(222) (322) (71) (81)
(321) (331) (332) (333)
(421) (422) (432)
(2221) (431) (441)
(521) (522)
(2222) (531)
(3221) (621)
(3311) (3222)
(3321)
(4221)
(4311)
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], Length[#]<=2*Median[#]&]], {n, 30}]
CROSSREFS
For maximum instead of median we have A237755.
For minimum instead of median we have A237800.
For maximum instead of length we have A361848.
The equal case is A362049.
A000041 counts integer partitions, strict A000009.
A000975 counts subsets with integer median.
A325347 counts partitions with integer median, complement A307683.
A359893 and A359901 count partitions by median.
A360005 gives twice median of prime indices, distinct A360457.
Sequence in context: A067859 A006207 A318403 * A334626 A339235 A332755
KEYWORD
nonn
AUTHOR
Gus Wiseman, Apr 10 2023
STATUS
approved