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proposed
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editing
proposed
The median of a multiset is either the middle part (for odd- length), or the average of the two middle parts (for even- length).
Table[Length[Select[IntegerPartitions[n], IntegerQ[Mean[#]]&&IntegerQ[Median[#]]&]], {n, 1, 30}]
A008284/A058398/A327482 count counts partitions by mean, see also A008284, A327482.
A237984 counts partitions containing their mean, strict A240850, ranked by A327473.
A359893/A359901/A359902 count partitions by median, ranked by A360005.
A360005(n)/2 gives median of prime indices.
Cf. A000016, A082550, A237984, A240219, `A316313, A326669, A327475, A349156, `A359889, A359894, A359897, A359905.
The median of a multiset is either the middle part (odd-length), or the average of the two middle parts (even-length).
allocated for Gus WisemanNumber of integer partitions of n with integer mean and integer median.
1, 2, 2, 4, 2, 8, 2, 10, 9, 14, 2, 39, 2, 24, 51, 49, 2, 109, 2, 170, 144, 69, 2, 455, 194, 116, 381, 668, 2, 1378, 2, 985, 956, 316, 2043, 4328, 2, 511, 2293, 6656, 2, 8634, 2, 8062, 14671, 1280, 2, 26228, 8035, 15991, 11614, 25055, 2, 47201, 39810, 65092
1,2
The a(1) = 1 through a(9) = 9 partitions:
1 2 3 4 5 6 7 8 9
11 111 22 11111 33 1111111 44 333
31 42 53 432
1111 51 62 441
222 71 522
321 2222 531
411 3221 621
111111 3311 711
5111 111111111
11111111
Table[Length[Select[IntegerPartitions[n], IntegerQ[Mean[#]]&&IntegerQ[Median[#]]&]], {n, 1, 30}]
For just integer mean we have A067538, strict A102627, ranked by A316413.
For just integer median we have A325347, strict A359907, ranked by A359908.
These partitions are ranked by A360009.
A000041 counts partitions, strict A000009.
A008284/A058398/A327482 count partitions by mean.
A051293 counts subsets with integer mean, median A000975.
A237984 counts partitions containing their mean, strict A240850, ranked by A327473.
A326567/A326568 gives mean of prime indices.
A326622 counts factorizations with integer mean, strict A328966.
A359893/A359901/A359902 count partitions by median, ranked by A360005.
Cf. A000016, A082550, A240219, `A316313, A326669, A327475, A349156, `A359889, A359894, A359897, A359905.
allocated
nonn
Gus Wiseman, Jan 21 2023
approved
editing
allocated for Gus Wiseman
allocated
approved