How to create array-based sequential numbering in Google Sheets based on adjacent column, skipping blanks?

In Google Sheets, how can I create an ARRAYFORMULA to generate sequential numbering in column B, only when adjacent C cell is not empty?

• I want to start sequential numbering from B10,
• If a cell in column C is blank, numbering in B cell be skipped, and then it continues from the next non-empty C cell.

Example:

I have found formulas for sequential numbering that ignore blank cells in the adjacent column, but these formulas need to be dragged down whenever new rows are added. I want to use ARRAYFORMULA so that it applies automatically to the entire range.

I tried using this formula generated by Claude:

=ARRAYFORMULA(IF(C10:C<>"", ROW(C10:C) - ROW(C10) + 1, ""))

This formula returns a blank in B cell when the adjacent C cell is empty, but it continues the numbering. So, in the table, it would show 4 - oranges , and , 5 - peach.

Here's one approach which you may adapt accordingly:

=map(C2:C,lambda(Σ,if(Σ="",,counta(C2:Σ))))

Alternative to try just in case those blank cells in Column_C are not true blank cells (which gives ISBLANK(<blank cell>)=false)

=map(C2:C,lambda(Σ,if(Σ="",,let(Σ,C2:Σ,counta(filter(Σ,Σ<>""))))))