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 A327591 Number of subsets of {1..n} containing no quotients of pairs of distinct elements. 6
 1, 2, 3, 5, 7, 13, 23, 45, 89, 137, 253, 505, 897, 1793, 3393, 6353, 9721, 19441, 35665, 71329, 129953, 247233, 477665, 955329, 1700417, 2657281, 5184001, 10368001, 19407361, 38814721, 68868353, 137736705, 260693505, 505830401, 999641601, 1882820609, 2807196673 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Fausto A. C. Cariboni, Table of n, a(n) for n = 0..167, (terms up to a(100) from Peter Kagey based on Andrew Howroyd's b-file for A326489) FORMULA A326489(n) + 1 for n > 0. EXAMPLE The a(0) = 1 through a(5) = 13 subsets:   {}  {}   {}   {}     {}     {}       {1}  {1}  {1}    {1}    {1}            {2}  {2}    {2}    {2}                 {3}    {3}    {3}                 {2,3}  {4}    {4}                        {2,3}  {5}                        {3,4}  {2,3}                               {2,5}                               {3,4}                               {3,5}                               {4,5}                               {2,3,5}                               {3,4,5} CROSSREFS Maximal subsets without quotients are A326492. Subsets with quotients are A326023. Subsets without differences or quotients are A326490. Subsets without products are A326489. Cf. A007865, A051026, A325860, A325994, A326079, A326117, A326491, A326496. Sequence in context: A185231 A080190 A076994 * A124147 A227627 A335116 Adjacent sequences:  A327588 A327589 A327590 * A327592 A327593 A327594 KEYWORD nonn AUTHOR Peter Kagey, Sep 17 2019 STATUS approved

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Last modified December 1 04:02 EST 2021. Contains 349426 sequences. (Running on oeis4.)