1. votive tablet depicting a math puzzle given in devotion to a shrine or temple by a wasan mathematicianSee also 和算 わさん
Wikipedia definition
2. SangakuSangaku or San Gaku are Japanese geometrical problems or theorems, in Euclidean geometry on wooden tablets which were placed as offerings at Shinto shrines or Buddhist temples during the Edo period (1603–1867) by members of all social classes.
Read “Sangaku” on English Wikipedia
Read “算額” on Japanese Wikipedia
Read “Sangaku” on DBpedia


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