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%I #10 Aug 30 2019 21:47:16
%S 1,2,3,5,9,17,25,49,73,145,217,433,553,1105,1657,2593,3937,7873,10057,
%T 20113,26689,42321,63481,126961,154801,309601,464401,737569,992161,
%U 1984321,2450881,4901761,6292801,10197313,15295969,26241697,32947489,65894977,98842465,161587873,205842529
%N Number of subsets of {1..n} containing all of their integer quotients.
%C These are sets that are closed under taking the quotient of two (not necessarily distinct) divisible terms.
%F For n > 0, a(n) = A326078(n) + 1.
%e The a(0) = 1 through a(5) = 17 subsets:
%e {} {} {} {} {} {}
%e {1} {1} {1} {1} {1}
%e {1,2} {1,2} {1,2} {1,2}
%e {1,3} {1,3} {1,3}
%e {1,2,3} {1,4} {1,4}
%e {1,2,3} {1,5}
%e {1,2,4} {1,2,3}
%e {1,3,4} {1,2,4}
%e {1,2,3,4} {1,2,5}
%e {1,3,4}
%e {1,3,5}
%e {1,4,5}
%e {1,2,3,4}
%e {1,2,3,5}
%e {1,2,4,5}
%e {1,3,4,5}
%e {1,2,3,4,5}
%t Table[Length[Select[Subsets[Range[n]],SubsetQ[#,Select[Divide@@@Tuples[#,2],IntegerQ]]&]],{n,0,10}]
%Y Cf. A007865, A051026, A054519, A067992, A103580, A325853, A325854, A325860, A325861, A325994, A326078.
%K nonn
%O 0,2
%A _Gus Wiseman_, Jun 04 2019
%E Terms a(21) and beyond from _Andrew Howroyd_, Aug 30 2019
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