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Solidus (/)
/ 𝕩: Indices
Repeat the index of each element in 𝕩 by the element's value. 𝕩 must be rank 1.
/ 1‿2‿3
/ 1‿0‿1
𝕨 / 𝕩: Replicate
Repeat each major cell in 𝕩 by the corresponding element in 𝕨.
Unit 𝕨 applies to all elements.
3 / "copy"
1‿0‿1 / 1‿2‿3