w 0 ( x ) {\displaystyle w_{0}(x)} is a zero-phase function (symmetrical about x = 0),[23] continuous for x ∈ [ − N / 2 , N / 2 ] , {\displaystyle x\in [-N/2,N/2],} where N is a positive integer (even or odd).[24] The sequence { w [ n ] = w 0 ( n − N / 2 ) , 0 ≤ n ≤ N } {\displaystyle \{w[n]=w_{0}(n-N/2),\quad 0\leq n\leq N\}} is symmetric, of length N + 1. {\displaystyle N+1.} { w [ n ] , 0 ≤ n ≤ N − 1 } {\displaystyle \{w[n],\quad 0\leq n\leq N-1\}} is DFT-symmetric, of length N . {\displaystyle N.} [upper-alpha 6]