A023585 Least odd prime divisor of 2*p(n)-1, or 1 if 2*p(n)-1 is a power of 2.

3, 5, 3, 13, 3, 5, 3, 37, 3, 3, 61, 73, 3, 5, 3, 3, 3, 11, 7, 3, 5, 157, 3, 3, 193, 3, 5, 3, 7, 3, 11, 3, 3, 277, 3, 7, 313, 5, 3, 3, 3, 19, 3, 5, 3, 397, 421, 5, 3, 457, 3, 3, 13, 3, 3, 3, 3, 541, 7, 3, 5, 3, 613, 3, 5, 3, 661, 673, 3, 17, 3, 3, 733, 5, 757, 3, 3, 13, 3, 19, 3