A364913 Number of integer partitions of n having a part that can be written as a nonnegative linear combination of the other (possibly equal) parts.
0, 0, 1, 2, 4, 5, 10, 12, 20, 27, 39, 51, 74, 95, 130, 169, 225, 288, 378, 479, 617, 778, 990, 1239, 1560, 1938, 2419, 2986, 3696, 4538, 5575, 6810, 8319, 10102, 12274, 14834, 17932, 21587, 25963, 31120, 37275, 44513, 53097, 63181, 75092, 89030, 105460, 124647
Offset: 0
Keywords
Examples
The a(0) = 0 through a(7) = 12 partitions: . . (11) (21) (22) (41) (33) (61) (111) (31) (221) (42) (322) (211) (311) (51) (331) (1111) (2111) (222) (421) (11111) (321) (511) (411) (2221) (2211) (3211) (3111) (4111) (21111) (22111) (111111) (31111) (211111) (1111111) The partition (5,4,3) has no part that can be written as a nonnegative linear combination of the others, so is not counted under a(12). The partition (6,4,3,2) has 6 = 4+2, or 6 = 3+3, or 6 = 2+2+2, or 4 = 2+2, so is counted under a(15).
Crossrefs
Programs
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Mathematica
combs[n_,y_]:=With[{s=Table[{k,i},{k,y},{i,0,Floor[n/k]}]},Select[Tuples[s],Total[Times@@@#]==n&]]; Table[Length[Select[IntegerPartitions[n],!UnsameQ@@#||Or@@Table[combs[#[[k]],Delete[#,k]]!={},{k,Length[#]}]&]],{n,0,15}]
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