Sequential numbering with gaps

[tghcogo]

Hi there.


I have a column in which I enter a date, and an adjacent column which automatically enters a sequential number, using ...

=IF(K10,J10+1,"")

this is fine providing every line has an entry, however I know want the same thing to happen if there are blanks in the date column:

481    7-nov
482    9-nov
blank  blank
blank  blank
483    9-nov
blank  blank
484    10-nov

I've tried several ways, but I think I'm overcomplicating, hopefully someone can point me in the right direction with a simple solution.

Thanks