Primality Checker - Just Basic

REM Semi-Primitive Primality checker (checks N by dividing through all prime numbers from 2 to sqrt(N)
REM JB 1.1
REM by Ahmed Fatoum

while (1) 'Infinite Loop
print 'new line
INPUT "Checking Primality from 2 till "; max 'input where to stop

if max = int(max) and max >= 2 then ' if max is a whole number and larger than 2
approx = int(max/log(max)) ' approximation of needed space (wikipedia: prime number theorem)
amount = approx +  int(((2.04) ^ Log(max))) ' some heap bonus so we dont run out of memory space
PRINT "Let's count to max: ";max;", Approximate Amount: ";approx;"+";amount-approx
' Code start
    DIM primes(amount) 'Reserve Memory space
''''''''''''''''''''''''''''''''''''''''''' VARS
    primes(0) = 2 ' 2 is hard coded for easifying purposes
    pntr = 0 'pointer to last non-zero value
    alig = 6 ' how many primes each line?
''''''''''''''''''''''''''''''''''''''''''' MAIN LOOP
start = time$("ms") 'Start Stopwatch

    for i = 2 to max 'Self-explainable
        for m = 0 to pntr 'from first recorded prime to last
            if (i mod primes(m) = 0 and i <> primes(pntr))  then 'break out of loop when 1 denominator is found
                exit for
            else 'we can substitute sqr(i) for pntr but this way we save time (e.g: 308 sec saved from 1->100,000)
                if primes(m) > sqr(i) then 'as stated above,for performance reasons we / through primes < sqr(number_to_check)
                    pntr = pntr+1 'increment pointer to pint to the newest prime number
                    primes(pntr) = i 'store a new prime
                        '''' OUTPUT START
                        If (x < alig-1) then
                            print primes(pntr), 'tabulator (horizontal space)
                            x = x + 1
                        else
                            print primes(pntr) 'line feed (newline)
                            x = 0
                        end if
                        '''' OUTPUT END
                    exit for 'we got our prime checked, checking till pntr is worth of time
                end if
            end if
        next m 'check if we can divide it through next prime
    next i 'k, on to the next

final = time$("ms") 'End Stopwatch
print 'line feed
print "Array has been filled with ";pntr;"/(";approx;"+";amount-approx;") primes in "; final-start ;" ms." ' statistics
else
if max = 0 then end
PRINT "please use a natural number >= 2"
end if
WEND
end