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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A326175 Number of minimal subsets of {1..n} containing n whose sum is greater than or equal to the sum of their complement.

Original entry on oeis.org

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

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Author

Gus Wiseman, Jun 11 2019

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}
		

Crossrefs

Programs

  • 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