import binascii
import simplesha3
hash = simplesha3.keccakc768 # SHA-3 winner with 384-bit output

p = 2^384 - 2^128 - 2^96 + 2^32 - 1 # standard NIST P-384 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 = 'CA9EBD338A9EE0E6862FD329062ABC06A793575A1C744F0EC24503A525F5D06E'
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 FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFF0000000000000000FFFFFFFF
# A FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFF0000000000000000FFFFFFFC
# B BADA55EC3BE2AD1F9EEEA5881ECF95BBF3AC392526F01D4CD13E684C63A17CC4D5F271642AD83899113817A61006413D