Backwards Read Primes are primes that when read backwards in base 10 (from right to left) 
are a different prime. (This rules out primes which are palindromes.)
```
Examples:
13 17 31 37 71 73 are Backwards Read Primes
```
13 is such because it's prime and read from right to left writes 31 which is prime too. Same for the others.

## Task
Find all Backwards Read Primes between two positive given numbers (both inclusive), the second one always being greater than or equal to the first one. The resulting array or the resulting string will be ordered following the natural order of the prime numbers.

## Example

backwardsPrime(2, 100) => [13, 17, 31, 37, 71, 73, 79, 97] 
backwardsPrime(9900, 10000) => [9923, 9931, 9941, 9967]
backwardsPrime(501, 599) => []

## Note for Forth
Return only the first backwards-read prime between start and end
or 0 if you don't find any

```python
backwards_prime(2, 100) => [13, 17, 31, 37, 71, 73, 79, 97] 
backwards_prime(9900, 10000) => [9923, 9931, 9941, 9967]
```

Difficulty: EASY
Tags: Mathematics

Starter code:
def backwardsPrime(start, stop):
	

Solutions:
def backwardsPrime(start, stop):
	primes = []
	for n in range(start, stop + 1):
		if n not in primes and is_prime(n) and is_prime(reverse(n)) and (n != reverse(n)):
			primes.append(n)
			if start <= reverse(n) <= stop:
				primes.append(reverse(n))
	return sorted(primes)

def is_prime(n):
	for i in range(2, int(n ** 0.5) + 1):
		if n % i == 0:
			return False
	return True

def reverse(n):
	return int(''.join(str(n)[::-1]))


def backwardsPrime(start, stop):
	is_prime = lambda n: all((n % a for a in range(3, 1 + int(n ** 0.5), 2))) if n > 2 and n % 2 else n == 2
	return [n for n in range(start + ~start % 2, stop + 1, 2) if is_prime(n) and n != int(str(n)[::-1]) and is_prime(int(str(n)[::-1]))]


def prime(a):
	if a == 2:
		return True
	if a < 2 or a % 2 == 0:
		return False
	return not any((a % x == 0 for x in range(3, int(a ** 0.5) + 1, 2)))

def backwardsPrime(start, nd):
	return [x for x in range(start, nd + 1) if str(x) != str(x)[::-1] and prime(x) and prime(int(str(x)[::-1]))]


def backwardsPrime(start, stop):
	return [x for x in range(start, stop + 1) if is_prime(x) and is_prime(int(str(x)[::-1])) and (str(x) != str(x)[::-1])]

def is_prime(n):
	return all((n % x for x in range(2, int(n ** 0.5 + 1))))


from math import sqrt
from itertools import count, islice

def isPrime(n):
	return n > 1 and all((n % i for i in islice(count(2), int(sqrt(n) - 1))))

def backwardsPrime(a, b):
	return [x for x in range(a, b + 1) if isPrime(x) and x > 10 and isPrime(int(str(x)[::-1])) and (int(str(x)[::-1]) != x)]


import math
KnownPrimes = []

def backwardsPrime(start, stop):
	k = math.ceil((start - 1) / 6)
	(Prime, p1, p2) = ([], 0, 0)
	while p1 <= stop or p2 <= stop:
		(p1, p2) = (6 * k - 1, 6 * k + 1)
		p1x = int(str(p1)[::-1])
		p2x = int(str(p2)[::-1])
		if not p1 == p1x and IsPrime(p1) and IsPrime(p1x) and (p1 <= stop):
			Prime.append(p1)
		if not p2 == p2x and IsPrime(p2) and IsPrime(p2x) and (p2 <= stop):
			Prime.append(p2)
		k = k + 1
	return Prime

def TryComposite(a, d, n, s):
	if pow(a, d, n) == 1:
		return False
	for i in range(s):
		if pow(a, 2 ** i * d, n) == n - 1:
			return False
	return True

def IsPrime(n, PrecisionForHugeN=16):
	if n in KnownPrimes or n in (0, 1):
		return True
	if any((n % p == 0 for p in KnownPrimes)):
		return False
	(d, s) = (n - 1, 0)
	while not d % 2:
		(d, s) = (d >> 1, s + 1)
	if n < 1373653:
		return not any((TryComposite(a, d, n, s) for a in (2, 3)))
	if n < 25326001:
		return not any((TryComposite(a, d, n, s) for a in (2, 3, 5)))
	if n < 118670087467:
		return [not any((TryComposite(a, d, n, s) for a in (2, 3, 5, 7))), False][n == 3215031751]
	if n < 2152302898747:
		return not any((TryComposite(a, d, n, s) for a in (2, 3, 5, 7, 11)))
	if n < 3474749660383:
		return not any((TryComposite(a, d, n, s) for a in (2, 3, 5, 7, 11, 13)))
	if n < 341550071728321:
		return not any((TryComposite(a, d, n, s) for a in (2, 3, 5, 7, 11, 13, 17)))
	return not any((TryComposite(a, d, n, s) for a in KnownPrimes[:PrecisionForHugeN]))


import math

def isPrime(n):
	checkNum = int(math.sqrt(n))
	for i in range(1, checkNum + 1):
		if n % i == 0 and i != 1:
			return False
	return True

def backwardsPrime(start, stop):
	backwardsPrimes = []
	for i in range(start, stop + 1):
		if isPrime(i) == True:
			reversedPrime = int(str(i)[::-1])
			if isPrime(reversedPrime) and reversedPrime != i:
				backwardsPrimes.append(i)
	return backwardsPrimes


def backwardsPrime(start, stop):
	output = []
	for x in range(start, stop + 1):
		if isPrime(x):
			if isReversePrime(x):
				output.append(x)
	return output

def isPrime(input):
	if input % 2 == 0:
		return False
	for x in range(3, int(input ** 0.5) + 1, 2):
		if input % x == 0:
			return False
	else:
		return True

def isReversePrime(input):
	tempstr = ''
	iptemp = str(input)
	i = len(iptemp) - 1
	while i >= 0:
		tempstr += iptemp[i]
		i = i - 1
	temp = 0
	temp = int(tempstr)
	if input == temp:
		return False
	if isPrime(temp):
		return True
	else:
		return False