According to this paper (http://arxiv.org/pdf/1601.02184v1.pdf http://arxiv.org/pdf/1601.02184v1.pdf), the entry for n=56 should also be one. Apparently, these

According to this paper (http://arxiv.org/pdf/1601.02184v1.pdf http://arxiv.org/pdf/1601.02184v1.pdf), the entry for n=56 should also be one. Apparently, these values come from a computer-assisted calculation from 1990, and the error wasn't discovered until 2014.