Greetings

I have sheet with some numbers in rows A1:A10
Number in adjacent rows can repeat so I want to color all rows having the
same values wih two alternating colours,

eg:
CELL VALUE ROW COLOUR
A1 1 WHITE
A2 1 WHITE
A3 4 GREY
A4 5 WHITE
A5 5 WHITE
A6 5 WHITE
A7 8 GREY
A8 10 WHITE
A9 10 WHITE
A10 12 GREY

i'e I want to alternatingly group and colour rows using only two colours eg
grey or white. The conditional formatting should only change colours when a
different value is found as rows are decended from top to bottom.

I have tried this formula (=$A1=$A2) but it sort of leaves out the boundary
cells

Any help will be appreciated