For the minimal counterexample to union closed sets conjecture, we have the lower bound $\mid$$\mathcal{A}$$\mid$ $\geq$ $4q1$ ($\mathcal{A}$ denotes the minimal counterexample family, $q$ denotes the number of elements in $\cup$$\mathcal{A}$). Is there any better lower bound? Is there any research/development happening towards this direction?
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1$\begingroup$ There is quite a bit of information at the Polymath wiki on Frankl's conjecture. $\endgroup$– Joseph O'RourkeCommented Feb 6, 2018 at 13:25

$\begingroup$ Yes indeed, thanks. But, under the section 'Partial results', it states the same inequality '$n$ $\leq$ $4m2$, assuming $\mathcal{A}$ is separating'. So, of not much help in this particular direction. $\endgroup$– SisyphusCommented Feb 6, 2018 at 13:41

2$\begingroup$ Which suggests that as of March 2016, when the page was last updated, no better bound was known. $\endgroup$– Joseph O'RourkeCommented Feb 6, 2018 at 17:26
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1 Answer
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The 2018 paper A lower bound for the minimal counterexample to Frankl’s conjecture by Ankush Hore improved the bound to: $$\mid\mathcal{A}\mid \geq 4q+1$$