Pretty sure it's not in the standard code.
You can modify the modules/Roster.php and add the following:
function memberslistmain()
{
$blob = "";
$count = 0;
$result = $this -> bot -> db -> select("SELECT nickname, last_seen FROM #___users LEFT JOIN alts ON #___users.nickname = alts.alt WHERE user_level = " . MEMBER . " AND alts.alt IS NULL ORDER BY nickname ASC");
if (!empty($result))
{
$inside = "##blob_title##:::: <botname>'s Mains List ::::##end##\n\n";
foreach ($result as $val)
{
$count++;
$inside .= "##blob_text##• " . $val[0];
if ($val[1] > 0)
{
$inside .= ", last seen at " . gmdate($this -> bot -> core("settings") -> get("Time", "FormatString"), $val[1]);
}
else
{
$inside .= ", never seen online";
}
$inside .= "##end## ".$this -> bot -> core("tools") -> chatcmd("whois " . $val[0], "[Whois]")."\n";
}
$blob = " :: " . $this -> bot -> core("tools") -> make_blob("click to view", $inside);
}
return $count . " mains in <botname>" . $blob;
}
You'd also have to change the command_handler code to allow for a !member main command.
Total Members: 
Guests: 868
Hidden: 0
Users: 0
