Drop Index produces "does not exist in the system catalog"

[LouBurgoyne]

I have run sp_helpindex 'TableName' on a table in a production database. It returns over 20 indexes with a description of "nonclustered, statistics, auto create located on PRIMARY"
These indexes cannot be dropped. "Drop Index TableName.IndexName produces "does not exist in the system catalog".
Questions:
1. Where are these indexes coming from?
2. Are they important?

Thanks
Lou Burgoyne

 

[tlbroadbent]

The statistics are auto created by SQL Server. They are important in optimizing queries. Although not recommended, you can drop statistics with the "DROP STATISTICS" statement. Set SQL BOL for details. Terry L. Broadbent
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