[go: up one dir, main page]

login
Revision History for A360245 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing all changes.
Number of integer partitions of n where the parts have the same median as the distinct parts.
(history; published version)
#5 by Michael De Vlieger at Mon Feb 06 10:06:07 EST 2023
STATUS

proposed

approved

#4 by Gus Wiseman at Mon Feb 06 00:12:06 EST 2023
STATUS

editing

proposed

#3 by Gus Wiseman at Mon Feb 06 00:11:43 EST 2023
MATHEMATICA

Table[Length[Select[IntegerPartitions[n], Median[#]==Median[Union[#]]&]], {n, 0, 30}]

CROSSREFS

For mean instead of median: A360242, ranked by ranks A360247, complement A360243.

These partitions are ranked by have ranks A360249.

The complement is A360244, ranked by ranks A360248.

A240219 counts partitions with mean equal to median, ranked by ranks A359889.

A325347 = counts partitions with w/ integer median, strict A359907, ranked by ranks A359908.

A359894 = counts partitions with mean different from median, ranked by ranks A359890.

Cf. A000975, A027193, `A067659, `A316313, ~`A326567/~`A326568, A326619/A326620, A326621, ~`A359895, `A359896, A359902, `A359906, `A360068, A360241, A360246, A360250, A360251.

#2 by Gus Wiseman at Sun Feb 05 19:44:59 EST 2023
NAME

allocated for Gus WisemanNumber of integer partitions of n where the parts have the same median as the distinct parts.

DATA

1, 1, 2, 3, 4, 4, 8, 6, 11, 13, 19, 19, 35, 33, 48, 66, 78, 88, 124, 138, 183, 219, 252, 306, 388, 450, 527, 643, 780, 903, 1097, 1266, 1523, 1784, 2107, 2511, 2966, 3407, 4019, 4667, 5559, 6364, 7492, 8601, 10063, 11634, 13469, 15469, 17985, 20558, 23812

OFFSET

0,3

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(8) = 11 partitions:

(1) (2) (3) (4) (5) (6) (7) (8)

(11) (21) (22) (32) (33) (43) (44)

(111) (31) (41) (42) (52) (53)

(1111) (11111) (51) (61) (62)

(222) (421) (71)

(321) (1111111) (431)

(2211) (521)

(111111) (2222)

(3221)

(3311)

(11111111)

For example, the partition y = (6,4,4,4,1,1) has median 4, and the distinct parts {1,4,6} also have median 4, so y is counted under a(20).

MATHEMATICA

Table[Length[Select[IntegerPartitions[n], Median[#]==Median[Union[#]]&]], {n, 0, 30}]

CROSSREFS

For mean instead of median: A360242, ranked by A360247, complement A360243.

These partitions are ranked by A360249.

The complement is A360244, ranked by A360248.

A000041 counts integer partitions, strict A000009.

A008284 counts partitions by number of parts.

A116608 counts partitions by number of distinct parts.

A240219 counts partitions with mean equal to median, ranked by A359889.

A325347 = partitions with integer median, strict A359907, ranked by A359908.

A359893 and A359901 count partitions by median.

A359894 = partitions with mean different from median, ranked by A359890.

A360071 counts partitions by number of parts and number of distinct parts.

Cf. A000975, A027193, `A067659, `A316313, ~`A326567/~`A326568, A326619/A326620, A326621, ~`A359895, `A359896, A359902, `A359906, `A360068, A360241, A360246, A360250, A360251.

KEYWORD

allocated

nonn

AUTHOR

Gus Wiseman, Feb 05 2023

STATUS

approved

editing

#1 by Gus Wiseman at Mon Jan 30 22:27:08 EST 2023
NAME

allocated for Gus Wiseman

KEYWORD

allocated

STATUS

approved