In the preamble of the 1818 sangaku tablet of Sugino'o Shrine, the proposers acknowledged the help of an unnamed teacher/master in understanding and solving certain mathematical problems. Endō Tadashi argued that this unnamed teacher could be Saitō Naonaka (1773-1844). In this paper, we examine the famous travel diary of Yamaguchi Kanzan (?-1850) especially on his second trip to the Northeast. We compare the content of Yamaguchi's diary with the three problems of Sugino'o's tablet. Together with the timing of Yamaguchi's travel, we conclude that Yamaguchi Kanzan was likely the unnamed master mentioned in the preface of the Sugino'o Shrine sangaku.

在 1818 年杉之尾神社三乐碑的序言中，提议者感谢一位未具名的老师/大师在理解和解决某些数学问题方面的帮助。远藤忠争辩说，这位未具名的老师可能是斋藤直中（1773-1844）。在本文中，我们考察了山口观山（？-1850 年）著名的旅行日记，特别是他第二次东北之行。我们将山口日记的内容与杉野尾的平板电脑的三个问题进行比较。结合山口来访的时间，我们推断山口观山很可能就是杉之尾神社散乐序言中提到的无名大师。