57233047domain: NAppears in sequencesOdd integers n such that 2^n == 16 (mod n).at n=13A033984Composite numbers k such that 2^(k-4) == 1 (mod k).at n=12A173138Odd numbers n such that 2^d(n) == 2^n (mod n) where d = A000005.at n=21A292562