Exemple #1
0
def islychrel(n):

    for _ in range(50):
        nr = int(''.join(reversed(str(n))))
        s = n + nr
        if ispalindromic(str(s)):
            return False
        else:
            n = s

    return True
Exemple #2
0
def islychrel(n):

    for _ in range(50):
        nr = int("".join(reversed(str(n))))
        s = n + nr
        if ispalindromic(str(s)):
            return False
        else:
            n = s

    return True
Exemple #3
0
                for b in range(10)] +\
           ['%d%d%d%d' % (a,b,b,a)  # 90 4-digit, same as 3-digit
                for a in range(1,10)
                for b in range(10)] +\
           ['%d%d%d%d%d' % (a,b,c,b,a) # 900 5-digit
                for a in range(1,10)
                for b in range(10)
                for c in range(10)] +\
           ['%d%d%d%d%d%d' % (a,b,c,c,b,a) # 900 6-digit, same as 5-digit
                for a in range(1,10)
                for b in range(10)
                for c in range(10)])

# This is much more efficient
print sum(i for i in palindromicnumbers()
        if i%2 and ispalindromic(dec2bin(i)))

# now I'm going to write it like crazy Lisp-ist ...

def palindromic(n):
    '''
    Generate palindromic numbers containing n digits
    '''
    return range(10) if n==1 else map(int, ('%d'*n % (comb + comb[::-1][n%2:])
        for comb in reduce(lambda ts, es: [t+(e,) for t in ts for e in es], 
        [[(t,) for t in range(1,10)]] + [range(10)]*(sum(divmod(n,2))-1))))


print sum(each for each in reduce(lambda x,y: x+y,
    (palindromic(i) for i in range(1,7)))
    if each % 2 and ispalindromic(dec2bin(each)))
Exemple #4
0
           ['%d%d%d%d' % (a,b,b,a)  # 90 4-digit, same as 3-digit
                for a in range(1,10)
                for b in range(10)] +\
           ['%d%d%d%d%d' % (a,b,c,b,a) # 900 5-digit
                for a in range(1,10)
                for b in range(10)
                for c in range(10)] +\
           ['%d%d%d%d%d%d' % (a,b,c,c,b,a) # 900 6-digit, same as 5-digit
                for a in range(1,10)
                for b in range(10)
                for c in range(10)])


# This is much more efficient
print sum(i for i in palindromicnumbers()
          if i % 2 and ispalindromic(dec2bin(i)))

# now I'm going to write it like crazy Lisp-ist ...


def palindromic(n):
    '''
    Generate palindromic numbers containing n digits
    '''
    return range(10) if n == 1 else map(
        int,
        ('%d' * n % (comb + comb[::-1][n % 2:])
         for comb in reduce(lambda ts, es: [t + (e, ) for t in ts for e in es],
                            [[(t, ) for t in range(1, 10)]] + [range(10)] *
                            (sum(divmod(n, 2)) - 1))))
Exemple #5
0
from euler import ispalindromic

print max(i*j 
        for i in range(100,1000) 
        for j in range(100,1000) 
        if ispalindromic(str(i*j)))