ZarankiewiczDB,

an online database of Zarankiewicz numbers.

z(27,29) = 155

By Damásdi, Héger and Szőnyi's recursive bound with $\alpha=1$ and $\beta=6$. [DHS13, p. 17]

upper bound = 155, submitted on April 23rd, 2016 (link)

By deleting 4 rows and 2 columns from the finite projective plane of order 5.

lower bound = 155, submitted on April 23rd, 2016 (link)

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