LizardSystems Wi-Fi Scanner uses the following naming convention for 802.11n and 802.11ac channels.

20 MHz channels are referenced by their channel number.
40 MHz channel is pair of 20 MHz channels (one 20 MHz primary channel, with a secondary channel above or below) is referenced in several ways:

Starting from version 4.0, LizardSystems Wi-Fi Scanner uses a short form of 802.11n channel names (e.g. 36,+1 or 40,-1).

802.11ac channels are referenced by their channel number center.

802.11ac 160 (80+80) MHz channels are referenced by two channel number centers separated by coma e.g. 42,106 or 106,138.