Problem: Sign of permutations

Code: Sign+of+permutations/tails_1643893872

Nibbles version: 0.2 | 0.21 | 0.22 | 0.23 | 0.24 | 0.25 | 1.00

Format: Compact | Simple | +Type | Table | JSON | .nbl (DeBruijn) | .nbl (names)

`* (product) 
    . (map) 
        `_ (subsequences) 
            ~ (auto = 2) 
            _ (= ints) 
        / (foldr1) <--arg( A ) 
            $ (= A) 
            `$ (signum) <--arg( C B ) 
                - (subtract) 
                    @ (= B) 
                    (implicit arg = C)