A365921 Triangle read by rows where T(n,k) is the number of integer partitions y of n such that k is the greatest member of {0..n} that is not the sum of any nonempty submultiset of y.
1, 1, 0, 1, 1, 0, 2, 0, 1, 0, 2, 0, 1, 2, 0, 4, 0, 0, 1, 2, 0, 5, 0, 0, 1, 1, 4, 0, 8, 0, 0, 0, 1, 2, 4, 0, 10, 0, 0, 0, 2, 1, 2, 7, 0, 16, 0, 0, 0, 0, 2, 1, 3, 8, 0, 20, 0, 0, 0, 0, 2, 2, 2, 4, 12, 0, 31, 0, 0, 0, 0, 0, 2, 2, 2, 5, 14, 0
Offset: 0
Examples
The partition (6,2,1,1) has subset-sums 0, 1, 2, 3, 4, 6, 7, 8, 9, 10 so is counted under T(10,5). Triangle begins: 1 1 0 1 1 0 2 0 1 0 2 0 1 2 0 4 0 0 1 2 0 5 0 0 1 1 4 0 8 0 0 0 1 2 4 0 10 0 0 0 2 1 2 7 0 16 0 0 0 0 2 1 3 8 0 20 0 0 0 0 2 2 2 4 12 0 31 0 0 0 0 0 2 2 2 5 14 0 39 0 0 0 0 0 4 2 2 3 6 21 0 55 0 0 0 0 0 0 4 2 4 3 9 24 0 71 0 0 0 0 0 0 5 4 2 4 5 10 34 0 Row n = 8 counts the following partitions: (4211) . . . (521) (611) (71) (8) . (41111) (5111) (431) (62) (3311) (53) (3221) (44) (32111) (422) (311111) (332) (22211) (2222) (221111) (2111111) (11111111)
Links
- Steven R. Finch, Monoids of natural numbers, March 17, 2009.
Crossrefs
Row sums are A000041.
Diagonal k = n-1 is A002865.
Central diagonal n = 2k is A126796 also.
This is the triangle for the rank statistic A365920.
Column sums are A366127.
A055932 lists numbers whose prime indices cover an initial interval.
A073491 lists numbers with gap-free prime indices.
A366128 gives the least non-subset-sum of prime indices.
Programs
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Mathematica
nmz[y_]:=Complement[Range[Total[y]],Total/@Subsets[y]]; Table[Length[Select[IntegerPartitions[n],Max@@Prepend[nmz[#],0]==k&]],{n,0,10},{k,0,n}]