RosettaCodeData/Task/Identity-matrix/Excel/identity-matrix.excel

IDMATRIX
=LAMBDA(n,
    LET(
        ixs, SEQUENCE(n, n, 0, 1),
        x, MOD(ixs, n),
        y, QUOTIENT(ixs, n),

        IF(x = y,
            1,
            0
        )
    )
)