x:y means there's y elements in slot x of a bucket, I think.

1 item requires exactly 10 comparisons to find.
8 items requires exactly 8 comparisons to find.
...

Update: No, the above is wrong.

x:y means there's y buckets with exactly x elements.

1 item requires exactly 10 comparisons to find.
1 items require exactly 9 comparisons to find.
8+1 items require exactly 8 comparisons to find.
...
382690+182129+58962+14525+2894+489+84+8+1 items require exactly 1 comparison to find.
406794 buckets are empty.