In the paper Patterson–Wiedemann construction revisited by Gangopadhyay et al. (2006), modifying an idempotent function , which corresponds to a (337,(127)(49))-interleaved sequence whose columns are either all 0’s or 1’s, a balanced function h having is obtained. In this short note, we find that dad14fb6318" title="Click to view the MathML source">Δf is computed incorrectly in their paper (leading to ) and correct their result by disproving the related conjecture for the 21-variable balanced functions.