A349796 Number of non-strict integer partitions of n with at least one part of odd multiplicity that is not the first or last.
0, 0, 0, 0, 0, 0, 0, 1, 2, 5, 8, 15, 23, 37, 52, 80, 109, 156, 208, 289, 378, 509, 654, 865, 1098, 1425, 1789, 2290, 2852, 3603, 4450, 5569, 6830, 8467, 10321, 12701, 15393, 18805, 22678, 27535, 33057, 39908, 47701, 57304, 68226, 81572, 96766, 115212, 136201
Offset: 0
Keywords
Examples
The a(7) = 1 through a(11) = 15 partitions: (3211) (4211) (3321) (5311) (4322) (32111) (4311) (6211) (4421) (5211) (32221) (5411) (42111) (33211) (6311) (321111) (43111) (7211) (52111) (42221) (421111) (43211) (3211111) (53111) (62111) (322211) (332111) (431111) (521111) (4211111) (32111111)
Crossrefs
Counting all non-strict partitions gives A047967.
The complement in non-strict partitions is A349795.
A003242 = Carlitz (anti-run) compositions.
A096441 = weakly alternating 0-appended partitions.
A349052 = weakly alternating compositions.
A349056 = weakly alternating permutations of prime indices.
A349798 = weakly but not strongly alternating permutations of prime indices.
Programs
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Mathematica
whkQ[y_]:=And@@Table[If[EvenQ[m],y[[m]]<=y[[m+1]],y[[m]]>=y[[m+1]]],{m,1,Length[y]-1}]; Table[Length[Select[IntegerPartitions[n],!whkQ[#]&&!whkQ[-#]&&!UnsameQ@@#&]],{n,0,30}]
Comments