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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
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.
Sequence in context: A185231 A080190 A076994 * A124147 A227627 A335116
KEYWORD
nonn
AUTHOR
Peter Kagey, Sep 17 2019
STATUS
approved