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There are only 3 non-overlapping channels 1 (2412MHz), 6 (2437MHz) and 11 (2462MHz). All others overlap significantly, causing adjacent-channel interference.
2.4GHz channels are 20 MHz wide. In the busy 2.4GHz range, using wider channels will often result in more interference and may not gain any throughput performance improvements. Check your environment before implementing wider channels.