Let F be a homogeneous polynomial of degree d in m + 1 variables defined over an algebraically closed field of characteristic 0 and suppose that F belongs to the sth secant variety of the d-uple Veronese embedding of into but that its minimal decomposition as a sum of dth powers of linear forms requires more than s summands. We show that if s ≤ d then F can be uniquely written as , where are linear forms with t ≤ (d-1)/2, and Q is a binary form such that with ’s linear forms and ’s forms of degree such that
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-ap108-3-2, author = {Edoardo Ballico and Alessandra Bernardi}, title = {Unique decomposition for a polynomial of low rank}, journal = {Annales Polonici Mathematici}, volume = {107}, year = {2013}, pages = {219-224}, zbl = {1297.14058}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ap108-3-2} }
Edoardo Ballico; Alessandra Bernardi. Unique decomposition for a polynomial of low rank. Annales Polonici Mathematici, Tome 107 (2013) pp. 219-224. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ap108-3-2/