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 A325880 Number of maximal subsets of {1..n} containing n such that every ordered pair of distinct elements has a different difference. 9
 1, 1, 2, 2, 4, 8, 8, 10, 18, 34, 50, 70, 78, 89, 120, 181, 277, 401, 561, 728, 867, 1031, 1219, 1537 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Also the number of maximal subsets of {1..n} containing n such that every orderless pair of (not necessarily distinct) elements has a different sum. LINKS EXAMPLE The a(2) = 1 through a(9) = 18 subsets:   {1,2}  {1,3}  {1,2,4}  {1,2,5}  {1,2,6}  {2,3,7}    {3,5,8}    {4,6,9}          {2,3}  {1,3,4}  {1,4,5}  {1,3,6}  {2,4,7}    {4,5,8}    {5,6,9}                          {2,3,5}  {1,4,6}  {2,6,7}    {1,2,4,8}  {1,2,4,9}                          {2,4,5}  {1,5,6}  {3,4,7}    {1,2,6,8}  {1,2,6,9}                                   {2,3,6}  {4,5,7}    {1,3,4,8}  {1,2,7,9}                                   {2,5,6}  {4,6,7}    {1,3,7,8}  {1,3,4,9}                                   {3,4,6}  {1,2,5,7}  {1,5,6,8}  {1,3,8,9}                                   {3,5,6}  {1,3,6,7}  {1,5,7,8}  {1,4,8,9}                                                       {2,3,6,8}  {1,6,7,9}                                                       {2,4,7,8}  {1,6,8,9}                                                                  {2,3,5,9}                                                                  {2,3,7,9}                                                                  {2,4,5,9}                                                                  {2,4,8,9}                                                                  {2,6,7,9}                                                                  {2,6,8,9}                                                                  {3,4,7,9}                                                                  {3,5,8,9} MATHEMATICA fasmax[y_]:=Complement[y, Union@@(Most[Subsets[#]]&/@y)]; Table[Length[fasmax[Select[Subsets[Range[n]], MemberQ[#, n]&&UnsameQ@@Subtract@@@Subsets[Union[#], {2}]&]]], {n, 0, 10}] CROSSREFS Cf. A002033, A108917, A143823, A143824, A196723. Cf. A325858, A325859, A325861, A325867, A325869, A325879, A325992. Sequence in context: A160159 A283241 A101651 * A132007 A094605 A217662 Adjacent sequences:  A325877 A325878 A325879 * A325881 A325882 A325883 KEYWORD nonn,more AUTHOR Gus Wiseman, Jun 02 2019 STATUS approved

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Last modified September 20 16:50 EDT 2021. Contains 347586 sequences. (Running on oeis4.)