Timeline for Minimal number of n/2-subsets of [n] that contains every d-subset
Current License: CC BY-SA 3.0
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| when toggle format | what | by | license | comment | |
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| Nov 1, 2017 at 12:08 | comment | added | Fedor Petrov | It is at least $2^d$ always by obvious reasons: $\binom{n}d/\binom{n/2}d=\prod_{i=0}^{d-1}\frac{n-i}{n/2-i}\geqslant 2^d$. | |
| Nov 1, 2017 at 3:15 | history | answered | Dustin G. Mixon | CC BY-SA 3.0 |