OFFSET
1,2
FORMULA
EXAMPLE
7 is absent from the list as Phi(7) == (x^3 + x + 1)*(x^3 + x^2 + 1) (mod 2).
MATHEMATICA
Select[Range[300], Transpose[Rest[FactorList[Cyclotomic[#, x], Modulus -> 2]]][[2]] == {1} &] (* T. D. Noe, Mar 03 2014 *)
PROG
(PARI) for(x=1, 200, if(polisirreducible(Mod(1, 2)*polcyclo(x)), print1(x", ")))
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Phil Carmody, May 21 2007
STATUS
approved