3002.sagews

#This is the given information along with
#the encrypted message blocks
n = 11481322877
r = 847018765
E1 = 6399300519
E2 = 4085097472
E3 = 3974468445
E4 = 8924762029
E5 = 2887101597
E6 = 3942013007 
E7 = 10043617708
E8 = 10379138936
E9 = 3995400497

#Find the factors of n
factor(n)

107033 * 107269

#Discover s using the factors of n
p = 107033
q = 107269
s = inverse_mod(r, (p-1) * (q-1))
print s

1394531365

D = list()
D.append(power_mod(E1, s, n))
D.append(power_mod(E2, s, n))
D.append(power_mod(E3, s, n))
D.append(power_mod(E4, s, n))
D.append(power_mod(E5, s, n))
D.append(power_mod(E6, s, n))
D.append(power_mod(E7, s, n))
D.append(power_mod(E8, s, n))
D.append(power_mod(E9, s, n))
print "These are the decrypted message blocks:"
print D

These are the decrypted message blocks: [2008050013, 1519200016, 1815120906, 903001301, 2008051301, 2009030901, 1400230119, 5180415, 1900000000]

#This is the key used for decoding the message blocks
key = {'00':' ', '01':'a', '02':'b', '03':'c', '04':'d', '05':'e', '06':'f', '07':'g', 
'08':'h', '09':'i', '10':'j', '11':'k', '12':'l', '13':'m', '14':'n', '15':'o', '16':'p', 
'17':'q', '18':'r', '19':'s', '20':'t', '21':'u', '22':'v', '23':'w', '24':'x', '25':'y', 
'26':'z'}

message = ""
for i in D:
    i = str(i)
    j = 0
    k = 0
    #append zeros to the front of the message block
    #in the case that the block has too few digits
    if len(i) < 10:
        temp = ""
        for j in range(10 - len(i)):
            temp += "0"
        i = temp + i
    #process the message block two digits at a time
    #and convert each digit pair into a letter
    while k < len(i):
        message += key[i[k] + i[k + 1]]
        k += 2
print "The secret message is:"
print message

The secret message is: the most prolific mathematician was erdos