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Recall that a space X is a c-semistratifiable (CSS) space, if the compact sets of X are G δ-sets in a uniform way. In this note, we introduce another class of spaces, denoting it by k-c-semistratifiable (k-CSS), which generalizes the concept of c-semistratifiable. We discuss some properties of k-c-semistratifiable spaces. We prove that a T 2-space X is a k-c-semistratifiable space if and only if X has a g function which satisfies the following conditions: (1) For each x 2 X, {x} = ∩{g(x, n): n 2 ℕ} and g(x, n + 1) {square image of or equal to} g(x, n) for each n ∈ ℕ. (2) If a sequence {xn} n∈ℕ of X converges to a point x ∈ X and y n ∈ g(x n, n) for each n ∈ ℕ, then for any convergent subsequence {y nk} k∈ℕ of {y n} n∈ℕ we have that {y nk} k∈ℕ converges to x. By the above characterization, we show that if X is a submesocompact locally k-csemistratifiable space, then X is a k-c-semistratifible space, and the countable product of k-c-semistratifiable spaces is a k-c-semistratifiable space. If X = ∪{Int(X n): n ∈ ℕ} and X n is a closed k-c-semistratifiable space for each n, then X is a k-c-semistratifiable space. In the last part of this note, we show that if X = ∪{X n: n ∈ ℕ} and X n is a closed strong β-space for each n ∈ ℕ, then X is a strong β-space.
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