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Bound for z(13,21)

Searching for matrices of weight greater than 67, all but 3 scaffolds were eliminated without search.

Scaffold $p=5$, $q=2$, $\mathbf{m}=(2,2,2,2,2)$, $\mathbf{n}=(5,5)$, $m_O=0$, $n_O=5$.

(0.363177163 seconds, score = 0, 2151 recursive calls, max depth = 27)

Scaffold $p=5$, $q=2$, $\mathbf{m}=(2,2,2,2,2)$, $\mathbf{n}=(4,4)$, $m_O=0$, $n_O=7$.

(6.98692E-4 seconds, score = 0, 0 recursive calls, max depth = 0)

Scaffold $p=5$, $q=2$, $\mathbf{m}=(2,2,2,2,2)$, $\mathbf{n}=(5,4)$, $m_O=0$, $n_O=6$.

(2.62634413 seconds, score = 0, 15418 recursive calls, max depth = 29)

upper bound = 67, submitted by Andrew Kay on April 22nd, 2016 (link)