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Let \(g\) and \(f\) be integer-valued functions defined on \(V(G)\) with \(f(v) \geq g(v) \geq 1\) for all \(v \in V(G)\). A graph \(G\) is called a \((g, f)\)-graph if \(g(v) \leq d_G(v) \leq f(v)\) for each vertex \(v \in V(G)\), and a \((g, f)\)-factor of a graph \(G\) is a spanning \((g, f)\)-subgraph of \(G\). A graph is \((g, f)\)-factorable if its edges can be decomposed into \((g, f)\)-factors.
The purpose of this paper is to prove the following three theorems: (i) If \(m \geq 2\), every \(\left((2mg+2m-2)t+(g+1)s, (2mf-2m+2)t+(f-1)s\right)\)-graph \(G\) is \((g, f)\)-factorable. (ii) Let \(g(x)\) be even and \(m > 2\). (1) If \(m\) is even, and \(G\) is a \(\left((2mg+2)t+(g+1)s, (2mf-2m+4)t+(f-1)s\right)\)-graph, then \(G\) is \((g, f)\)-factorable; (2) If \(m\) is odd, and \(G\) is a \(((2mg+4)t+(g+1)s$, $(2mf-2m+2)t+(f-1)s)\)-graph, then \(G\) is \((g, f)\)-factorable. (iii) Let \(f(x)\) be even and \(m > 2\). (1) If \(m\) is even, and \(G\) is a \(\left((2mg+2m-4)t+(g+1)s, (2mf-2)t+(f-1)s\right)\)-graph, then \(G\) is \((g, f)\)-factorable;
(2) If \(m\) is odd, and \(G\) is a \(((2mg+2m-2)t+(g+1)s\), \((2mf-4)t+(f-1)s)\)-graph, then \(G\) is \((g, f)\)-factorable.
where \(t\), \(m\) are integers and \(s\) is a nonnegative integer.