import binascii
import simplesha3
hash = simplesha3.keccakc512 # SHA-3 winner with 256-bit output

p = 2^224 - 2^96 + 1 # standard NIST P-224 prime
k = GF(p)

def secure(A,B):
  n = EllipticCurve([k(A),k(B)]).cardinality()
  return (n.is_prime() and (2*p+2-n).is_prime()
    and Integers(n)(p).multiplicative_order() * 100 >= n-1
    and Integers(2*p+2-n)(p).multiplicative_order() * 100 >= 2*p+2-n-1)

def str2int(seed):
  return Integer(seed.encode('hex'),16)

A = p-3
S = '3CC520E9434349DF680A8F4BCADDA648D693B2907B216EE55CB4853DB68F9165'
B = str2int(hash(binascii.unhexlify(S))) # verifiably random
if secure(A,B):
  print 'p',hex(p).upper()
  print 'A',hex(A).upper()
  print 'B',hex(B).upper()

# output:
# p FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF000000000000000000000001
# A FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFE
# B BADA55ECFD9CA54C0738B8A6FB8CF4CCF84E916D83D6DA1B78B622351E11AB4E