A383708 Number of integer partitions of n such that it is possible to choose a family of pairwise disjoint strict integer partitions, one of each part.
1, 1, 2, 2, 3, 5, 5, 7, 8, 13, 14, 18, 22, 27, 36, 41, 50, 61, 73, 86
Offset: 0
Examples
For y = (3,3) we can choose disjoint strict partitions ((2,1),(3)), so (3,3) is counted under a(6). The a(1) = 1 through a(9) = 8 partitions: (1) (2) (3) (4) (5) (6) (7) (8) (9) (2,1) (3,1) (3,2) (3,3) (4,3) (4,4) (5,4) (4,1) (4,2) (5,2) (5,3) (6,3) (5,1) (6,1) (6,2) (7,2) (3,2,1) (4,2,1) (7,1) (8,1) (4,3,1) (4,3,2) (5,2,1) (5,3,1) (6,2,1)
Crossrefs
Programs
-
Mathematica
pof[y_]:=Select[Join@@@Tuples[IntegerPartitions/@y], UnsameQ@@#&]; Table[Length[Select[IntegerPartitions[n], pof[#]!={}&]],{n,15}]
Comments