欧拉项目python代码(12--)

第12题：

拥有超过500个因数的第一个三角数（1+2+3+4+......)

def findivisionnum(num): count = 0 n=1 import math while count<num: count = 0 for i in range(1,int(math.sqrt(triangle(n)))+1): if not triangle(n)%i: count +=2 if int(math.sqrt(triangle(n)))==math.sqrt(triangle(n)): count -=1 n += 1 return triangle(n-1) def triangle(n): return n*(n+1)/2

print findivisionnum(500)

[Finished in 13.9s]

第14题：

def findlength(n):

    count = 0

    while n!=1:

        if not n%2:

            n /=2

            count +=1

        else:

            n =3*n+1

            count +1

    countcopy=count

    count=0

    return countcopy





def lengthmax(num):

    i=1

    max_count=1

    max_number=0

    while i<=num:

        if max_count<findlength(i):

            max_count=findlength(i)

            max_number=i

            i +=1

        else:

            i +=1

    return max_number





print lengthmax(1000000)

第15题：

def findsum1(num1):

    root=1

    for i in range(1,2*num+1):

        root *= i

    for i in range(1,num+1):

        root /= i

        root /= i

    return root



print findrout(20)