Japanese poetry important Edo period (1603 and 1867, also known as "Tokugawa") and modern times; however, the history of poetry often is different than socio-political history. Since the middle of the 19th century, the major forms of Japanese poetry have been "tanka" (the modern name for "waka"), "haiku" and "shi" or western-style poetry. Today, the main forms of Japanese poetry include both experimental poetry and poetry that seeks to revive traditional ways. Poets writing in tanka, haiku and shi may seldom write poetry other than in their specific chosen form, although some active poets are eager to collaborate with poets in other
Invariant of a binary form for the ring of covariants. showed that the ring of invariants of a degree 8 form is generated by 9 invariants of degrees 2, 3, 4, 5, 6, 7, 8, 9, 10, and the ring of covariants is generated by 69 covariants. August von Gall () and confirmed the generators for the ring of invariants and showed that the ideal of relations between them is generated by elements of degrees 16, 17, 18, 19, 20. showed that the algebra of invariants of a degree 9 form is generated by 92 invariants. Cröni, Hagedorn, and Brouwer computed 476 covariants, and Lercier