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 A325859 Number of maximal subsets of {1..n} such that every orderless pair of distinct elements has a different product. 12
 1, 1, 1, 1, 1, 1, 4, 4, 11, 11, 28, 28, 60, 60, 140, 241, 299, 299, 572, 572, 971 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,7 LINKS EXAMPLE The a(1) = 1 through a(9) = 11 subsets:   {1}  {12}  {123}  {1234}  {12345}  {2356}   {23567}   {123457}  {235678}                                      {12345}  {123457}  {123578}  {1234579}                                      {12456}  {124567}  {124567}  {1235789}                                      {13456}  {134567}  {125678}  {1245679}                                                         {134567}  {1256789}                                                         {134578}  {1345679}                                                         {135678}  {1345789}                                                         {145678}  {1356789}                                                         {234578}  {1456789}                                                         {235678}  {2345789}                                                         {245678}  {2456789} MATHEMATICA fasmax[y_]:=Complement[y, Union@@(Most[Subsets[#]]&/@y)]; Table[Length[fasmax[Select[Subsets[Range[n]], UnsameQ@@Times@@@Subsets[#, {2}]&]]], {n, 0, 15}] CROSSREFS The subset case is A196724. The maximal case is A325859. The integer partition case is A325856. The strict integer partition case is A325855. Heinz numbers of the counterexamples are given by A325993. Cf. A002033, A108917, A143823, A275972, A325858, A325860, A325861, A325869, A325878, A325879, A325880. Sequence in context: A168373 A266438 A128499 * A265206 A327684 A231064 Adjacent sequences:  A325856 A325857 A325858 * A325860 A325861 A325862 KEYWORD nonn,more AUTHOR Gus Wiseman, May 31 2019 STATUS approved

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Last modified March 29 20:20 EDT 2020. Contains 333117 sequences. (Running on oeis4.)