Let $S$ be a subset of positive integers. Show that no such set $S$ exist.












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Let $S$ be a subset of positive integers, such that for any positive integer $n$, there exist a unique pair of integer of $a, b$ in $S$ such that $a+2b=n$. Show that no such set $S$ exist. (Hint: Show that it has no minimal element)










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    Welcome to MSE! This seems to be a homework question; you'll find that "do my homework" questions are generally not well-received here. Please edit the question to include your progress. This will show other users that you have actually attempted the problem and put some effort into it, as well as allow them to help you based on where you are stuck.
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    – platty
    Dec 1 '18 at 6:49






  • 5




    $begingroup$
    Are you sure that you have the problem correct? Taking $n = 1$ should show that this immediately fails.
    $endgroup$
    – platty
    Dec 1 '18 at 6:50
















0












$begingroup$


Let $S$ be a subset of positive integers, such that for any positive integer $n$, there exist a unique pair of integer of $a, b$ in $S$ such that $a+2b=n$. Show that no such set $S$ exist. (Hint: Show that it has no minimal element)










share|cite|improve this question









$endgroup$








  • 2




    $begingroup$
    Welcome to MSE! This seems to be a homework question; you'll find that "do my homework" questions are generally not well-received here. Please edit the question to include your progress. This will show other users that you have actually attempted the problem and put some effort into it, as well as allow them to help you based on where you are stuck.
    $endgroup$
    – platty
    Dec 1 '18 at 6:49






  • 5




    $begingroup$
    Are you sure that you have the problem correct? Taking $n = 1$ should show that this immediately fails.
    $endgroup$
    – platty
    Dec 1 '18 at 6:50














0












0








0





$begingroup$


Let $S$ be a subset of positive integers, such that for any positive integer $n$, there exist a unique pair of integer of $a, b$ in $S$ such that $a+2b=n$. Show that no such set $S$ exist. (Hint: Show that it has no minimal element)










share|cite|improve this question









$endgroup$




Let $S$ be a subset of positive integers, such that for any positive integer $n$, there exist a unique pair of integer of $a, b$ in $S$ such that $a+2b=n$. Show that no such set $S$ exist. (Hint: Show that it has no minimal element)







combinatorics






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share|cite|improve this question










asked Dec 1 '18 at 6:47









tedzzztedzzz

1




1








  • 2




    $begingroup$
    Welcome to MSE! This seems to be a homework question; you'll find that "do my homework" questions are generally not well-received here. Please edit the question to include your progress. This will show other users that you have actually attempted the problem and put some effort into it, as well as allow them to help you based on where you are stuck.
    $endgroup$
    – platty
    Dec 1 '18 at 6:49






  • 5




    $begingroup$
    Are you sure that you have the problem correct? Taking $n = 1$ should show that this immediately fails.
    $endgroup$
    – platty
    Dec 1 '18 at 6:50














  • 2




    $begingroup$
    Welcome to MSE! This seems to be a homework question; you'll find that "do my homework" questions are generally not well-received here. Please edit the question to include your progress. This will show other users that you have actually attempted the problem and put some effort into it, as well as allow them to help you based on where you are stuck.
    $endgroup$
    – platty
    Dec 1 '18 at 6:49






  • 5




    $begingroup$
    Are you sure that you have the problem correct? Taking $n = 1$ should show that this immediately fails.
    $endgroup$
    – platty
    Dec 1 '18 at 6:50








2




2




$begingroup$
Welcome to MSE! This seems to be a homework question; you'll find that "do my homework" questions are generally not well-received here. Please edit the question to include your progress. This will show other users that you have actually attempted the problem and put some effort into it, as well as allow them to help you based on where you are stuck.
$endgroup$
– platty
Dec 1 '18 at 6:49




$begingroup$
Welcome to MSE! This seems to be a homework question; you'll find that "do my homework" questions are generally not well-received here. Please edit the question to include your progress. This will show other users that you have actually attempted the problem and put some effort into it, as well as allow them to help you based on where you are stuck.
$endgroup$
– platty
Dec 1 '18 at 6:49




5




5




$begingroup$
Are you sure that you have the problem correct? Taking $n = 1$ should show that this immediately fails.
$endgroup$
– platty
Dec 1 '18 at 6:50




$begingroup$
Are you sure that you have the problem correct? Taking $n = 1$ should show that this immediately fails.
$endgroup$
– platty
Dec 1 '18 at 6:50










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