bent function

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bent function

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So called because they are as different as possible from all linear functions (the simplest or "straight-line" functions) and from all affine functions (which preserve parallel lines).

bent function (plural bent functions)

1. (combinatorics) A Boolean function ${\displaystyle f:\mathbb {Z} _{2}^{n}\to \mathbb {Z} _{2}}$ whose Walsh transform has constant absolute value.