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Erdős Problem 361

Reference: erdosproblems.com/361

open Filter namespace Erdos361

Let $c > 0$ and $n$ be some large integer. What is the size of the largest set $A \subseteq {1, \ldots, \lfloor c n \rfloor}$ such that $n$ is not a sum of a subset of $A$? Does this depend on $n$ in an irregular way?

@[category research open, AMS 11] theorem declaration uses 'sorry'erdos_361.bigO (c : ) (hc : 0 < c) (A : ) (hA : c n, A n = ((Finset.Icc 1 c * n⌋₊).powerset.filter (fun B n a B, a)).sup Finset.card) : (fun n (A n : )) =O[atTop] (answer(sorry) : ) := c:hc:0 < cA: hA: (c n : ), A n = {B (Finset.Icc 1 c * n⌋₊).powerset | n a B, a}.sup Finset.card(fun n => (A n)) =O[atTop] sorry All goals completed! 🐙

Let $c > 0$ and $n$ be some large integer. What is the size of the largest set $A \subseteq {1, \ldots, \lfloor c n \rfloor}$ such that $n$ is not a sum of a subset of $A$? Does this depend on $n$ in an irregular way?

@[category research open, AMS 11] theorem declaration uses 'sorry'erdos_361.bigTheta (c : ) (hc : 0 < c) (A : ) (hA : c n, A n = ((Finset.Icc 1 c * n⌋₊).powerset.filter (fun B n a B, a)).sup Finset.card) : (fun n (A n : )) =Θ[atTop] (answer(sorry) : ) := c:hc:0 < cA: hA: (c n : ), A n = {B (Finset.Icc 1 c * n⌋₊).powerset | n a B, a}.sup Finset.card(fun n => (A n)) =Θ[atTop] sorry All goals completed! 🐙

Let $c > 0$ and $n$ be some large integer. What is the size of the largest set $A \subseteq {1, \ldots, \lfloor c n \rfloor}$ such that $n$ is not a sum of a subset of $A$? Does this depend on $n$ in an irregular way?

@[category research open, AMS 11] theorem declaration uses 'sorry'erdos_361.smallO (c : ) (hc : 0 < c) (A : ) (hA : c n, A n = ((Finset.Icc 1 c * n⌋₊).powerset.filter (fun B n a B, a)).sup Finset.card) : (fun n (A n : )) =o[atTop] (answer(sorry) : ) := c:hc:0 < cA: hA: (c n : ), A n = {B (Finset.Icc 1 c * n⌋₊).powerset | n a B, a}.sup Finset.card(fun n => (A n)) =o[atTop] sorry All goals completed! 🐙 end Erdos361