select number+1 as rowid,number*6+1 as rowbeg,number*6+6 as rowend 
from master.dbo.spt_values
where type='P'

select * from v$version
 
BANNER                                                                         
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production   
PL/SQL Release 11.2.0.2.0 - Production                                         
CORE 11.2.0.2.0 Production                                                     
TNS for 64-bit Windows: Version 11.2.0.2.0 - Production                        
NLSRTL Version 11.2.0.2.0 - Production                                         
 
5 rows selected.

SELECT tab.RN +1   AS "ROWID",
        tab.RN *6+1 AS ROWBEG,
        tab.RN*6+6 AS ROWEND
   from  (
     SELECT (rownum -1) rn
       FROM DUAL
      connect by rownum < 15
      ) tab;

select 1 as rnum, 1 as rowbeg, 6 as rowend from dual
union all
select rownum+1 as rnum,rownum*6+1 as rowbeg,rownum*6+6 as rowend
from all_objects

SQL> select level, 6*(level-1)+1, 6*level from dual connect by level <= 10;
     LEVEL 6*(LEVEL-1)+1    6*LEVEL
---------- ------------- ----------
         1             1          6
         2             7         12
         3            13         18
         4            19         24
         5            25         30
         6            31         36
         7            37         42
         8            43         48
         9            49         54
        10            55         60