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A327591 Number of subsets of {1..n} containing no quotients of pairs of distinct elements.

%I A327591 #17 Dec 06 2020 15:56:19
%S A327591 1,2,3,5,7,13,23,45,89,137,253,505,897,1793,3393,6353,9721,19441,
%T A327591 35665,71329,129953,247233,477665,955329,1700417,2657281,5184001,
%U A327591 10368001,19407361,38814721,68868353,137736705,260693505,505830401,999641601,1882820609,2807196673
%N A327591 Number of subsets of {1..n} containing no quotients of pairs of distinct elements.
%H A327591 Fausto A. C. Cariboni, <a href="/A327591/b327591.txt">Table of n, a(n) for n = 0..167</a>, (terms up to a(100) from Peter Kagey based on Andrew Howroyd's b-file for A326489)
%F A327591 A326489(n) + 1 for n > 0.
%e A327591 The a(0) = 1 through a(5) = 13 subsets:
%e A327591   {}  {}   {}   {}     {}     {}
%e A327591       {1}  {1}  {1}    {1}    {1}
%e A327591            {2}  {2}    {2}    {2}
%e A327591                 {3}    {3}    {3}
%e A327591                 {2,3}  {4}    {4}
%e A327591                        {2,3}  {5}
%e A327591                        {3,4}  {2,3}
%e A327591                               {2,5}
%e A327591                               {3,4}
%e A327591                               {3,5}
%e A327591                               {4,5}
%e A327591                               {2,3,5}
%e A327591                               {3,4,5}
%Y A327591 Maximal subsets without quotients are A326492.
%Y A327591 Subsets with quotients are A326023.
%Y A327591 Subsets without differences or quotients are A326490.
%Y A327591 Subsets without products are A326489.
%Y A327591 Cf. A007865, A051026, A325860, A325994, A326079, A326117, A326491, A326496.
%K A327591 nonn
%O A327591 0,2
%A A327591 _Peter Kagey_, Sep 17 2019