Not an an SDF sadly. @henryseg, do you have an implicit definition f(w,x,y,z)=0 around that is equivalent to your parametric version? I can try making A(t) a function of z, see how far I can go. But you've probably been there already.
Proof: Arranging 1³+2³+3³+4³+5³+6³+…+n³ in the plane: 1×1²+2×2²+3×3²+4×4²+5×5²+6×6²+…+nxn² The even squares overlap (🟨) but also leave uncovered gaps (🟥) and 🟨=🟥 pic.twitter.com/To8e3DlW6a