A326175 Number of minimal subsets of {1..n} containing n whose sum is greater than or equal to the sum of their complement.
1, 1, 1, 3, 3, 5, 10, 14, 25, 44, 71, 128, 231, 411, 740, 1352, 2481, 4570, 8390, 15550, 29103, 54345, 101312, 190316, 359827, 679051, 1279956, 2426200, 4621174, 8789565, 16701225, 31871629, 61052515, 116818123, 223333533, 428435056, 824395640, 1584833707, 3044562148, 5865073390, 11326741619, 21857561924
Offset: 1
Keywords
Examples
The a(1) = 1 through a(8) = 14 subsets: {1} {2} {3} {1,4} {3,5} {5,6} {1,6,7} {3,7,8} {2,4} {4,5} {1,4,6} {2,5,7} {4,6,8} {3,4} {1,2,5} {2,3,6} {2,6,7} {4,7,8} {2,4,6} {3,4,7} {5,6,8} {3,4,6} {3,5,7} {5,7,8} {3,6,7} {6,7,8} {4,5,7} {1,2,7,8} {4,6,7} {1,3,6,8} {5,6,7} {1,4,5,8} {1,2,4,7} {2,3,5,8} {2,3,6,8} {2,4,5,8} {3,4,5,8} {1,2,3,4,8}
Programs
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Mathematica
fasmin[y_]:=Complement[y,Union@@Table[Union[s,#]&/@Rest[Subsets[Complement[Union@@y,s]]],{s,y}]]; Table[Length[fasmin[Select[Subsets[Range[n]],MemberQ[#,n]&&Plus@@#>=Plus@@Complement[Range[n],#]&]]],{n,10}]
Extensions
a(15)-a(42) from Bert Dobbelaere, Jun 22 2019