Serial number of sales tax invoice and service tax! india?

serial number is an internal control. it will not Create any problem. but it is always suggested to keep different serial for easy reach. you can create two type of sales voucher in tally and resolved your problem.
you are using Tally sofware for your business. there is provision in Tally itself to give Invoice Numbers Manually. that way you can segrigate sales Invoice and Service Tax Invoice.
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