250583domain: NPropertiesPrimalityPrimeyesAppears in sequencesNumbers whose base-12 representation has exactly 6 runs.at n=10A043655Numbers k such that 2^(k-1) == 1 + b*k (mod k^2), where b divides k - 2^p for some integer p >= 0 and 2^p <= b.at n=57A186884Prime numbersat n=22080