MAXN = 20
TIMES = 10000'00

't0=time$("ms")
FOR n = 1 TO MAXN
    avg = FNtest(n, TIMES)
    theory = FNanalytical(n)
    diff = (avg / theory - 1) * 100
    PRINT n, avg, theory, using("##.####",diff); "%"
NEXT
't1=time$("ms")
'print t1-t0; " ms"
END

function FNanalytical(n)
    FOR i = 1 TO n
        s = s+ FNfactorial(n) / n^i / FNfactorial(n-i)
    NEXT
    FNanalytical = s
end function

function FNtest(n, times)
    FOR i = 1 TO times
        x = 1 : b = 0
        WHILE (b AND x) = 0
            c = c + 1
            b = b OR x
            x = 2^int(n*RND(1))
        WEND
    NEXT
    FNtest = c / times
end function

function FNfactorial(n)
    IF n=1 OR n=0 THEN FNfactorial=1 ELSE FNfactorial= n * FNfactorial(n-1)
end function