463 in progress

gistfile1.txt

#Define the function f by recursion:
def f(n):
    if n==1:
        return 1
    if n==3:
        return 3
    if n%2==0:
        return f(n/2)
    if (n-1)%4==0:
        m=(n-1)/4
        return 2*f(2*m+1)-f(m)
    if (n-3)%4==0:
        m=(n-3)/4
        return 3*f(2*m+1)-2*f(m)
def s(n):
    ans=0
    for m in xrange(1,n+1):
        ans+=f(m)
    return ans 
print s(3**37)