However you don’t need such small primes. Your goal is to find a modulus that lets you compute discrete logs. Using the Pohlig-Hellman algorithm you want it to factor into primes each of which is small enough to let you solve the DL problem modulo that prime. Using straightforward DL algorithms for those sub-problems, like Pollard rho, takes time proportional to the square root of the prime size. If you can afford to spend say 2^40 time to find a discrete log, this lets you use primes of up to 80 bits in size.

For such primes, u = 1152/80 or 14.4, and u^u is about 2^56, so it would take you that many tries to find such a modulus. Again that’s way too long.

If you are willing to take longer on your discrete log, say up to 2^64 time (maybe you’re a super spy agency), you could use primes up to 128 bits and u = 1152/128, for u^u = 400 million which would be doable for such an organization.

If you just want to come up with a factorable number in about 2000 tries, which is about as much time as you took to create your table, that requires a u of about 4.828 and a prime size of 1152/4.828 or 239 bits. That’s about the best you could hope for in terms of smooth moduli, that you might find one all of whose factors are less than 239 bits, if you try 2000 times.

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