Game of life in F#

GameOfLife.fs

open System
open System.Threading

let printBoard (grid:int[,]) =
  let maxX = (Array2D.length1 grid) - 1
  let maxY = (Array2D.length2 grid) - 1
  for row in 0 .. maxX do
    for col in 0 .. maxY do
      if(grid.[row,col] = 1) then printf "*|" else printf " |"
    printfn ""

let tick oldBoard =
  let width = (Array2D.length1 oldBoard) - 1
  let height = (Array2D.length2 oldBoard) - 1
  oldBoard |> 
    Array2D.mapi (fun x y cell ->
                    let xMin = if(x-1 < 0) then width - 1 else x-1
                    let xMax = if(x+1 > width - 1) then 0 else x+1
                    let yMin = if(y-1 < 0) then height - 1 else y-1
                    let yMax = if(y+1 > height - 1) then 0 else y+1
    
                    let v1 = oldBoard.[xMin, yMin]
                    let v2 = oldBoard.[x, yMin]
                    let v3 = oldBoard.[xMax, yMin]
    
                    let v4 = oldBoard.[xMin, y]
                    let v5 = oldBoard.[xMax, y]
    
                    let v6 = oldBoard.[xMin, yMax]
                    let v7 = oldBoard.[x, yMax]
                    let v8 = oldBoard.[xMax,yMax]
    
                    if(cell = 1) then
                        if(v1+v2+v3+v4+v5+v6+v7+v8 < 2 || v1+v2+v3+v4+v5+v6+v7+v8 > 3) then 0 else 1
                    else
                        if(v1+v2+v3+v4+v5+v6+v7+v8 = 3) then 1 else 0
                    )

[<EntryPoint>]
let main argv = 
    let rng = new System.Random((int)System.DateTime.UtcNow.Ticks)
    let width = 25
    let height = 25
    let mutable board = Array2D.init width height (fun _ _ -> if(rng.NextDouble() > 0.5) then 1 else 0)
    let mutable continueLooping = true

    while continueLooping do 
      Console.Clear() |> ignore
      printBoard board
      board <- tick board
      Thread.Sleep(250)
      if(Console.KeyAvailable) then
        let cki = Console.ReadKey(true)
        if(cki.Key = ConsoleKey.Escape) then continueLooping <- false

    printfn "COMPLETE"
    Console.ReadLine() |> ignore
    0 // return an integer exit code