Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_30931 ( "No. overall" real, "No. for series" real, "Title" text, "Directed by" text, "Written by" text, "Original air date" text, "UK viewers (million)" text )

### Question ###
What episode number of the series is 'the coming of arthur (part 1)'?

### Accurate SQL ###

SELECT "No. for series" FROM table_30931 WHERE "Title" = 'The Coming of Arthur (Part 1)'