A162018 Numbers n for which 2^^n != 2^2^n (mod n); for the "^^" notation see A092188.
7, 9, 11, 13, 19, 21, 22, 23, 25, 27, 29, 31, 33, 35, 37, 38, 39, 41, 45, 47, 49, 50, 53, 54, 55, 57, 59, 61, 62, 63, 65, 66, 67, 69, 71, 73, 74, 75, 77, 79, 81, 82, 83, 86, 87, 89, 91, 92, 93, 94, 95, 97, 98, 99, 101, 103, 105, 106, 107, 108, 109, 110, 111, 113, 114, 115
Offset: 1
Examples
7 is in the sequence because 2^2^7 = 2^128 == 4 mod 7, but 2^^7 = 2^2^2^2^2^2^2 == 2 mod 7.
Links
- Robert Munafo, 2^^N == 2^(2^N) mod N