user: Question: What is the S Registered User, when Userpics Free is 6 [free] or 15 [plus]?
Columns: ['Name', 'Year Began', 's Registered user', 'Updated in past 30 days', 'Registration', 'Ability to syndicate off-site feeds', 'Userpics Free', 'Userpics Paid', 'Monthly Cost for Paid Account', 'Yearly Cost for Paid Account', 'Permanent Account']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Asks', '2006', '13127', '31', 'Open', 'Unknown', '3', 'Unknown', 'Unknown', 'Unknown', 'Unknown']
SQL:

assistant: SELECT "s Registered user" FROM "Table" WHERE "Userpics Free" = '6 [free] or 15 [plus]';