how do you lua

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function pe1()
sum = 0
for x = 0,999 do
  if x%5==0 or x%3==0 then
    sum = sum+x
  end
end
print(sum)
end

function pe2()
sum = 0
last = 1
fib = 1
while fib<4000000 do
  if fib%2==0 then
    sum = sum+fib
  end
  a = last
  last = fib
  fib = fib+a
end
print(sum)
end

function pe3()--: find lagest prime factor
math = require "math"

function isprimev2(x)
  for n = 2,math.sqrt(x) do
    if x%n==0 then
      return false
    end
  end
  return true
end
function isfac(x,n)
  return x%n==0
end
lpf = 0
for x = 0,600851475143^(1/2) do
  if isfac(600851475143,x) then
    if isprimev2(x) then
      lpf = x
    end
  end
end
print('final')
print(lpf)
end

function pe4()
lpn = 0 
for x = 100,999 do
  for y = 100,999 do
    z = tostring(x*y)
    if z == string.reverse(z) then
      if x*y>lpn then
        lpn = x*y
      end
    end
  end
end
print(lpn)
end

function pe5()
sedn = 1
temp = 1
--sedn = smallest evenly divisible number
x = 1
while(x<=20) do
  if sedn%x==0 then
    sedn = sedn
    x=x+1
    temp = sedn
  else
    sedn = sedn+temp
  end
end
print('sedn:', sedn)
end
--pe6 is already done

function pe7()
primes = 0
try = 1
function isprime(x)
  for n=2,math.sqrt(x) do
    if x%n==0 then
      return false
    end
  end
  return true
end
while(primes<10001) do
  try = try+1
  if isprime(try) then
    primes=primes+1
  end
end
print(try)
end

function pe9()
for a = 1 , 1000 do
  for b= 1, 1000 do
    for c=1,1000 do
      if a<b and b<c then
        if a+b+c==1000 then
          if a*a+b*b==c*c then
            print(a*b*c)
          end
        end
      end
    end
  end
end
end

function pe10()
function isprime(x)
  for n=2,math.sqrt(x) do
    if x%n==0 then
      return false
    end
  end
  return true
end
sum = 0
for x = 1,1000000 do
  x = x*2-1
  if isprime(x) then
    sum = sum+x
  end
end
print(sum)
end
pe10()