Smallest k such that 2^^n is not congruent to 2^^(n-1) mod k, where 2^^n denotes the power tower 2^2^...^2 (in which 2 appears n times).
A027763
Smallest k such that 2^^n is not congruent to 2^^(n-1) mod k, where 2^^n denotes the power tower 2^2^...^2 (in which 2 appears n times).
Terms
- a(0) =2a(1) =3a(2) =5a(3) =11a(4) =23a(5) =47a(6) =283a(7) =719a(8) =1439a(9) =2879a(10) =34549a(11) =138197a(12) =531441a(13) =1594323a(14) =4782969a(15) =14348907a(16) =43046721a(17) =86093443a(18) =344373773a(19) =688747547a(20) =3486784401
External references
- oeis: A027763