If the paper says nothing then they probably just didn’t think about it. You can extend a 32-bit seed to 64 bits in various ways, and some may yield better results than others. If the paper mentions any seed extension strategies for wider numbers, then maybe you can adapt them to 32->64.
If not, why not try something like !X, X, where ! is bitwise or and X is your 32-bit seed.
If the paper says nothing then they probably just didn’t think about it. You can extend a 32-bit seed to 64 bits in various ways, and some may yield better results than others. If the paper mentions any seed extension strategies for wider numbers, then maybe you can adapt them to 32->64.
If not, why not try something like !X, X, where ! is bitwise or and X is your 32-bit seed.