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Challenges Expand a polynomial

BQN, 15 bytes ⊢(«∘⊢-×)´˜1∾˜≠˜ A 3-train (fold with initial): we zero list of the same length as the input with a one appended (the base case), then for each root we do the multiplication by the...

posted 11d ago by panadestein‭

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#1: Initial revision by user avatar panadestein‭ · 2025-03-19T20:54:55Z (11 days ago)
# [BQN], 15 bytes

    ⊢(«∘⊢-×)´˜1∾˜≠˜

A 3-train (fold with initial): we zero list of the same length as the input with a one appended (the base case), then for each root we do the multiplication by the variable (a shift), and the multiplication by the number. Coefficients in descending order

[BQN online REPL][Try]

[BQN]: https://mlochbaum.github.io/BQN/
[Try]: https://mlochbaum.github.io/BQN/try.html#code=UCDihpAg4oqiKMKr4oiY4oqiLcOXKcK0y5wx4oi+y5ziiaDLnApQwqgg4p+o4p+o4p+pLCBbMV0sIFsxLCAyXSwgWzEsIDFdLCBbMSwgMiwgM13in6k=