def is_redundant_multiplicon(self, value):
        """ Returns True if the passed multiplicon ID is redundant, False
            otherwise.

            - value, (int) multiplicon ID
        """
        if not hasattr(self, '_redundant_multiplicon_cache'):
            sql = '''SELECT id FROM multiplicons WHERE is_redundant="-1"'''
            cur = self._dbconn.cursor()
            cur.execute(sql, {'id': str(value)})
            result = [int(r[0]) for r in cur.fetchall()]
            self._redundant_multiplicon_cache = set(result)
        if value in self._redundant_multiplicon_cache:
            return True
        else:
            return False
Returns True if the passed multiplicon ID is redundant, False
            otherwise.

            - value, (int) multiplicon ID