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 A326492 Number of maximal subsets of {1..n} containing no quotients of pairs of distinct elements. 5
 1, 1, 2, 2, 3, 3, 4, 4, 4, 5, 7, 7, 10, 10, 16, 18, 31, 31, 47, 47, 52, 62, 104, 104, 130, 159, 283, 283, 323, 323, 554, 554, 616, 690, 1248, 1366, 1871, 1871, 3567, 3759, 5245, 5245, 8678, 8678, 9808, 12148, 23352, 23352, 27470, 31695, 45719, 47187, 54595, 54595, 95383, 108199 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS FORMULA a(n) = A326496(n) + 1 for n > 1. - Andrew Howroyd, Aug 30 2019 EXAMPLE The a(0) = 1 through a(9) = 5 subsets:   {}  {1}  {1}  {1}   {1}   {1}    {1}     {1}      {1}       {1}            {2}  {23}  {23}  {235}  {235}   {2357}   {23578}   {23578}                       {34}  {345}  {256}   {2567}   {25678}   {256789}                                    {3456}  {34567}  {345678}  {345678}                                                               {456789} MATHEMATICA fasmax[y_]:=Complement[y, Union@@(Most[Subsets[#]]&/@y)]; Table[Length[fasmax[Select[Subsets[Range[n]], Intersection[#, Divide@@@Select[Tuples[#, 2], UnsameQ@@#&&Divisible@@#&]]=={}&]]], {n, 0, 10}] CROSSREFS Subsets with quotients are A326023. Subsets with quotients > 1 are A326079. Subsets without quotients are A327591. Maximal subsets without differences or quotients are A326491. Maximal subsets without quotients (or products) are A326496. Cf. A007865, A121269, A325860, A325994, A326117, A326489, A326490. Sequence in context: A181988 A194173 A028825 * A132924 A076890 A103358 Adjacent sequences:  A326489 A326490 A326491 * A326493 A326494 A326495 KEYWORD nonn AUTHOR Gus Wiseman, Jul 09 2019 EXTENSIONS Terms a(16) and beyond from Andrew Howroyd, Aug 30 2019 STATUS approved

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Last modified September 21 12:57 EDT 2020. Contains 337272 sequences. (Running on oeis4.)