Kenichi Nakajima1, Koichi Okuda2, Koji Maruyama3,4. 1. Department of Nuclear Medicine/Functional Imaging and Artificial Intelligence, Kanazawa University, 13-1 Takara-machi, Kanazawa, 920-8640, Japan. nakajima@med.kanazawa-u.ac.jp. 2. Department of Physics, Kanazawa Medical University, Kahoku, Japan. 3. Wolfram Research Inc., Tokyo, Japan. 4. Department of Chemistry and Materials Science, Osaka City University, Osaka, Japan.