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check less n primes (good, better methods)
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import math | |
def tri_prime(n): | |
primes = [2] | |
def is_prime(number): | |
if number % 2 == 0: return False | |
for i in range(3, math.floor(number / 2) + 1): | |
if number % i == 0: | |
return False | |
return True | |
for i in range(3, n + 1): | |
if is_prime(i): | |
primes.append(i) | |
return primes | |
def good_prime(n): | |
primes = [2] | |
def is_prime(number): | |
if number % 2 == 0 and n > 2: | |
return False | |
return all(number % i for i in range(3, int(math.sqrt(number)) + 1, 2)) | |
for i in range(3, n + 1): | |
if is_prime(i): | |
primes.append(i) | |
return primes | |
def better_prime(n): | |
primes = [2] | |
def is_prime(number): | |
if number % 2 == 0: return False | |
sqrt_n = int(math.sqrt(number)) | |
for p in primes: | |
if p > sqrt_n: return True | |
if number % p == 0: return False | |
if sqrt_n <= primes[-1]: | |
return True | |
elif sqrt_n > primes[-1]: | |
# almost do not | |
return all(number % j for j in range(primes[-1], sqrt_n + 1, 2)) | |
for i in range(3, n + 1): | |
if is_prime(i): | |
primes.append(i) | |
return primes | |
def odd_prime(n): | |
primes = [2, 3] | |
def is_prime(number): | |
if number % 2 == 0 or number % 3 == 0: return False | |
x = int((number - 3) / 2) | |
y = 1 | |
for i in range(x, 1, -3): | |
if i >= y: | |
if y != 1 and i % y == 0: | |
return False | |
else: | |
break | |
y += 2 | |
return True | |
for i in range(5, n + 1): | |
if is_prime(i): | |
primes.append(i) | |
return primes |
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