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 A285572 Number of finite sets of pairwise indivisible positive integers with least common multiple n. 75
 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 3, 1, 2, 2, 1, 1, 3, 1, 3, 2, 2, 1, 4, 1, 2, 1, 3, 1, 9, 1, 1, 2, 2, 2, 6, 1, 2, 2, 4, 1, 9, 1, 3, 3, 2, 1, 5, 1, 3, 2, 3, 1, 4, 2, 4, 2, 2, 1, 23, 1, 2, 3, 1, 2, 9, 1, 3, 2, 9, 1, 10, 1, 2, 3, 3, 2, 9, 1, 5, 1, 2, 1, 23, 2, 2, 2, 4, 1, 23, 2, 3, 2, 2, 2, 6, 1, 3, 3, 6 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,6 LINKS Michael De Vlieger, Table of n, a(n) for n = 1..10000 EXAMPLE The a(72)=10 sets are {72}, {8,9}, {8,18}, {8,36}, {9,24}, {18,24}, {24,36}, {6,8,9}, {8,9,12}, {8,12,18}. MATHEMATICA nn=50; stableSets[u_, Q_]:=If[Length[u]===0, {{}}, With[{w=First[u]}, Join[stableSets[DeleteCases[u, w], Q], Prepend[#, w]&/@stableSets[DeleteCases[u, r_/; r===w||Q[r, w]||Q[w, r]], Q]]]]; Table[Length[Select[Rest[stableSets[Divisors[n], Divisible]], LCM@@#===n&]], {n, 1, nn}] CROSSREFS Cf. A000666, A006126, A048143, A054921, A076078, A076413, A285573. Sequence in context: A168324 A303838 A324837 * A179926 A066882 A300831 Adjacent sequences:  A285569 A285570 A285571 * A285573 A285574 A285575 KEYWORD nonn AUTHOR Gus Wiseman, Apr 21 2017 STATUS approved

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Last modified May 12 06:54 EDT 2021. Contains 343820 sequences. (Running on oeis4.)