Reserving the following k's from n=1 to 1M (including DC of Gary's work):
612509
671413
685183
686711
700057
Also reserving k=963643 to at least n=2M, k=10453199 to at least n=3.5M, k=10813783 to at least n=1M, and k=1665624349782373 to n=1.5M, including DCs from n=1.
