Describe [ sqrt(3) r1^n/6 - sqrt(3) r2^n? here.

lib/config.php:156: Notice: Undefined variable: accept

lib/DbaDatabase.php:143: Warning: dba_insert() [<a href='function.dba-insert'>function.dba-insert</a>]: You cannot perform a modification to a database without proper access

lib/DbaDatabase.php:160: Warning: DbaDatabase: store[insert](p[ sqrt(3) r1^n/6 - sqrt(3) r2^n)

lib/DbaDatabase.php:143: Warning: dba_insert() [<a href='function.dba-insert'>function.dba-insert</a>]: You cannot perform a modification to a database without proper access