2.3: Big-Omega Notation
- Page ID
- 49264
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For non-negative functions, \(f(n)\) and \(g(n)\), if there exists an integer \(n_{0}\) and a constant \(c>0\) such that for all integers \(n>n_{0}\), \(f(n)\geq cg(n)\), then \(f(n)\) is \(\Omega (g(n))\). This is denoted as \(f(n)=\Omega (g(n))\).
This is almost the same definition as Big Oh, except that \(f(n)\geq cg(n)\), this makes \(g(n)\) a lower bound function, instead of an upper bound function. It describes the best that can happen for a given data size.