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Deligne–Lusztig Character

Given a connected reductive group G\mathbf{G} and an FF-stable maximal torus Tw\mathbf{T}_w (parameterised by an element ww of the Weyl group WW), the Deligne–Lusztig character RTw(1)R_{\mathbf{T}_w}(1) is the virtual character of G(Fq)\mathbf{G}(\mathbb{F}_q) obtained by \ell-adic cohomology of the Deligne–Lusztig variety associated to ww. This tool expands RTw(1)R_{\mathbf{T}_w}(1) in the basis of unipotent characters, displaying the integer inner products γ,RTw(1)\langle \gamma, R_{\mathbf{T}_w}(1)\rangle for each unipotent character γ\gamma. The torus Tw\mathbf{T}_w can be specified either by choosing a ϕ\phi-conjugacy class of WW from a drop-down list, or by typing a word in the Coxeter generators (with 1-based indices, separated by spaces).