A generalized Euler sequence over a complete normal variety
X is the unique extension of the trivial bundle
V ⊗ \mathcal{O}
X by the sheaf of differentials Ω
X, given by the inclusion of a linear space
V ⊂ Ext
1X(\mathcal{O}
X, Ω
X). For Λ, a lattice of Cartier divisors, let ℛ
Λ denote the corresponding sheaf associated to
V spanned by the first Chern classes of divisors in Λ. We prove that any projective, smooth variety on which the bundle ℛ
Λ splits into a direct sum of line bundles is toric. We describe the bundle ℛ
Λ in terms of the sheaf of differentials on the characteristic space of the Cox ring, provided it is finitely generated. Moreover, we relate the finiteness of the module of sections of ℛ
Λ and of the Cox ring of Λ.
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