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A343344 Number of integer partitions of n that are either empty, or do not have smallest part dividing all the others, but do have greatest part divisible by all the others. 9
1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 1, 1, 5, 1, 6, 4, 6, 7, 15, 6, 16, 15, 20, 17, 36, 18, 43, 36, 46, 48, 72, 45, 93, 82, 103, 88, 152, 104, 179, 158, 191, 194, 285, 202, 328, 292, 373, 348, 502, 391, 576, 519, 659, 634, 864, 665 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,18
COMMENTS
Alternative name: Number of integer partitions of n with no part dividing all the others, but with a part divisible by all the others.
LINKS
EXAMPLE
The a(18) = 1 through a(23) = 15 partitions (A..E = 10..14):
633222 C43 C332 C432 C64 E72
A522 66332 A5222 A552 F53
C322 633332 C3222 C433 I32
66322 6332222 663222 C3322 C443
633322 6333222 663322 C632
6322222 63222222 6333322 66632
63322222 C3332
C4322
663332
A52222
C32222
6333332
6632222
63332222
632222222
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], #=={}||!And@@IntegerQ/@(#/Min@@#)&&And@@IntegerQ/@(Max@@#/#)&]], {n, 0, 30}]
CROSSREFS
The second condition alone gives A130689.
The half-opposite versions are A130714 and A343342.
The first condition alone gives A338470.
The Heinz numbers of these partitions are 1 and A343339.
The opposite version is A343345.
The strict case is A343380.
A000009 counts strict partitions.
A000041 counts partitions.
A000070 counts partitions with a selected part.
A006128 counts partitions with a selected position.
A015723 counts strict partitions with a selected part.
Sequence in context: A201419 A163336 A173898 * A200644 A318265 A318553
KEYWORD
nonn
AUTHOR
Gus Wiseman, Apr 15 2021
STATUS
approved

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Last modified June 1 21:15 EDT 2024. Contains 373029 sequences. (Running on oeis4.)