How to get Manhattan cells' values around another cell by radius?

Question

I'm having some issues finding an algorithm to get the cells' values around a cell.

Here is a picture I modified explaining the situation :

I want to put in a table all the light blue values, that are around the dark blue cell in a radius of x (3 in the picture).

I tried to find some formulas on the Internet and also here but found nothing.

Answer 1

local cell = 369
local r = 3
for x = -r, r do 
    for y = -r, r do 
        if math.abs(x) + math.abs(y) <= r then 
            local new_cell = cell + 29*math.floor(x/2) - 27*math.floor(y/2) + (x+y)%2 * (math.floor(cell/14)%2 + 14*(x%2-y%2)) + x*(x+y+1)%2
            print(new_cell)
        end 
    end 
end