A script to generate checker board

checker.fs

let buildCell j i =
    if j % 2 = 0 && i % 2 = 0 || j % 2 = 1 && i % 2 = 1
    then
        "0"
    else
        "1"

let buildRow j n =
    [0 .. n]
    |> List.map (fun i -> buildCell j i)
    |> String.concat ""

let checkers n =
    [0 .. n]
    |> List.map(fun j -> buildRow j n)
    |> String.concat "\n"

checkers 3 |> printfn "%s"