f499a1c0_quences_in_Oracle__autonumber___Description
[Parameter] INCREMENT BY [Example] INCREMENT BY 1 [Description] 
Specify the interval between sequence numbers. This integer value can be any positive or negative integer, but it cannot be 0. This value can have 28 or fewer digits. The absolute of this value must be less than the difference of MAXVALUE and MINVALUE. If this value is negative, then the sequence descends. If the increment is positive, then the sequence ascends. If you omit this clause, the interval defaults to 1.
How to use sequences in Oracle (autonumber)
Description