1. Advanced Institute for Materials Research, Tohoku University, Sendai, 980-8557, Japan.
2. Center for Advanced Intelligence Project, RIKEN, Tokyo, 103-0027, Japan, and Department of Mathematics, Keio University, Yokohama, 223-8522, Japan.
3. Center for Data Science, Ehime University, Matsuyama, 790-8577, Japan, and Center for Advanced Intelligence Project, RIKEN, Tokyo, 103-0027, Japan.