A367214 Number of strict integer partitions of n whose length (number of parts) is equal to the sum of some submultiset.
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, 97, 113, 132, 153, 178, 205, 238, 272, 315, 360, 413, 471, 539, 613, 698, 792, 899, 1018, 1153, 1302, 1470, 1658, 1867, 2100, 2362, 2652, 2974, 3335, 3734, 4178, 4672
Offset: 0
Keywords
Examples
The strict partition (6,4,3,2,1) has submultisets {1,4} and {2,3} with sum 5 so is counted under a(16). The a(1) = 1 through a(10) = 5 strict partitions: (1) . (2,1) . (3,2) (4,2) (5,2) (6,2) (7,2) (8,2) (3,2,1) (4,2,1) (4,3,1) (4,3,2) (5,3,2) (5,2,1) (5,3,1) (6,3,1) (6,2,1) (7,2,1) (4,3,2,1)
Crossrefs
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.
sum-full sum-free comb-full comb-free
-------------------------------------------
Triangles:
Programs
-
Mathematica
Table[Length[Select[IntegerPartitions[n], UnsameQ@@#&&MemberQ[Total/@Subsets[#], Length[#]]&]], {n,0,30}]
Comments