The prime 41, can be written as the sum of six consecutive primes:
\[41 = 2 + 3 + 5 + 7 + 11 + 13\]This is the longest sum of consecutive primes that adds to a prime below one-hundred.
The longest sum of consecutive primes below one-thousand that adds to a prime, contains 21 terms, and is equal to 953.
Which prime, below one-million, can be written as the sum of the most consecutive primes? import math
PRIME_LIST = []
PRIME_RANGE = 545
def is_Prime(number):
if number < 2:
return False
for x in range(2, int(math.sqrt(number)) + 1):
if number % x == 0:
return False
return True
prime_count = 0
index = 1
while prime_count < PRIME_RANGE + 1:
if is_Prime(index):
PRIME_LIST.append(index)
prime_count += 1
index += 1
max_count = 0
final_result = 0
start = 0
while start < PRIME_RANGE and PRIME_RANGE - start > max_count:
result = 0
count = 0
for prime in PRIME_LIST[start:]:
if result + prime >= 1000000:
break
count += 1
result += prime
if is_Prime(result):
if count > max_count:
max_count = count
final_result = result
start += 1
print max_count, final_result
在处理循环跳出条件上转了几圈 PRIME_RANGE = 545 这是一个知道答案之后输入的magic number 关于素数的好几题我都在纠结，使用一个素数表可以加快效率，但是，究竟需要多大的素数表也是一个问题