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Number of strict integer partitions of n whose length (number of parts) is equal to the sum of some submultiset.
24

%I #8 Nov 13 2023 08:46:33

%S 1,1,0,1,0,1,2,2,3,4,5,5,7,8,10,12,14,17,21,25,30,36,43,51,60,71,83,

%T 97,113,132,153,178,205,238,272,315,360,413,471,539,613,698,792,899,

%U 1018,1153,1302,1470,1658,1867,2100,2362,2652,2974,3335,3734,4178,4672

%N Number of strict integer partitions of n whose length (number of parts) is equal to the sum of some submultiset.

%C These partitions have Heinz numbers A367224 /\ A005117.

%e The strict partition (6,4,3,2,1) has submultisets {1,4} and {2,3} with sum 5 so is counted under a(16).

%e The a(1) = 1 through a(10) = 5 strict partitions:

%e (1) . (2,1) . (3,2) (4,2) (5,2) (6,2) (7,2) (8,2)

%e (3,2,1) (4,2,1) (4,3,1) (4,3,2) (5,3,2)

%e (5,2,1) (5,3,1) (6,3,1)

%e (6,2,1) (7,2,1)

%e (4,3,2,1)

%t Table[Length[Select[IntegerPartitions[n], UnsameQ@@#&&MemberQ[Total/@Subsets[#], Length[#]]&]], {n,0,30}]

%Y The following sequences count and rank integer partitions and finite sets according to whether their length is a subset-sum or linear combination of the parts. The current sequence is starred.

%Y sum-full sum-free comb-full comb-free

%Y -------------------------------------------

%Y partitions: A367212 A367213 A367218 A367219

%Y strict: A367214* A367215 A367220 A367221

%Y subsets: A367216 A367217 A367222 A367223

%Y ranks: A367224 A367225 A367226 A367227

%Y A000041 counts integer partitions, strict A000009.

%Y A088809/A093971/A364534 count certain types of sum-full subsets.

%Y A188431 counts complete strict partitions, incomplete A365831.

%Y A240855 counts strict partitions whose length is a part, complement A240861.

%Y A275972 counts strict knapsack partitions, non-strict A108917.

%Y A364272 counts sum-full strict partitions, sum-free A364349.

%Y A365925 counts subset-sums of strict partitions, non-strict A304792.

%Y Triangles:

%Y A008289 counts strict partitions by length, non-strict A008284.

%Y A365661 counts strict partitions with a subset-sum k, non-strict A365543.

%Y A365832 counts strict partitions by subset-sums, non-strict A365658.

%Y Cf. A002865, A126796, A237113, A237668, A238628, A363225, A364346, A364350, A364533, A365311, A365922.

%K nonn

%O 0,7

%A _Gus Wiseman_, Nov 12 2023