BQN, 15 bytes^SBCS

-˜`⍟(≠-1˙)≡≠↑1˙

Try it here.

Unlike many array languages, BQN doesn't have a binomial primitive, so a more creative solution is required.

-˜`⍟(≠-1˙)≡≠↑1˙ #
-˜`             # swapped minus scan
   ⍟(≠-1˙)      # repeated input length-1 times
          ≡     # matches
           ≠↑1˙ # input length take 1 (ex: 1‿0‿0‿0 ≡ 4↑1)

BQN, 15 13 bytes^SBCS

-2 bytes thanks to Marshall Lochbaum

-˜`⍟≠≡1‿¯1⥊˜≠

Try it here.

Unlike many array languages, BQN doesn't have a binomial primitive, so a more creative solution is required.

-˜`⍟≠≡1‿¯1⥊˜≠ #
-˜`           # swapped minus scan
   ⍟≠         # repeated input length number of times
     ≡        # matches
      1‿¯1⥊˜≠ # alternating 1,-1 .. extended to the input length