A153514 Terms of A122780 which are not Carmichael numbers A002997.

1, 6, 66, 91, 121, 286, 671, 703, 726, 949, 1541, 1891, 2665, 2701, 3281, 3367, 3751, 4961, 5551, 7107, 7381, 8205, 8401, 8646, 11011, 12403, 14383, 15203, 15457, 16471, 16531, 18721, 19345, 23521, 24046, 24661, 24727, 28009, 29161, 30857, 31621

Offset

1,2

Comments

For the intersection of this sequence and A153508, see A153513.

Links

Robert Israel, Table of n, a(n) for n = 1..1000

Maple

filter:= proc(n) local p;
  if isprime(n) or (3 &^n - 3 mod n <> 0) then return false fi;
  if n::even then return true fi;
  if not numtheory:-issqrfree(n) then return true fi;
  for p in numtheory:-factorset(n) do
    if n-1 mod (p-1) <> 0 then return true fi
  od;
false
end proc:
filter(1):= true:
select(filter, [$1..10^5]); # Robert Israel, Jan 29 2017

Mathematica

okQ[n_] := !PrimeQ[n] && PowerMod[3, n, n] == Mod[3, n] && Mod[n, CarmichaelLambda[n]] != 1;
Select[Range[10^5], okQ] (* Jean-François Alcover, Mar 27 2019 *)

Crossrefs

Cf. A002997, A122780, A153508, A153513.

Sequence in context: A110222 A119230 A122780 * A119144 A153087 A117794

Adjacent sequences: A153511 A153512 A153513 * A153515 A153516 A153517

Keyword

nonn

Author

Artur Jasinski, Dec 28 2008

Status

approved