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A207671 Numbers in ternary representation that match nonzero polynomials with all coefficients in {0,1,2} that are irreducible modulo 3.

%I A207671 #9 Aug 19 2021 10:56:46
%S A207671 10,11,12,20,21,22,101,112,122,202,211,221,1021,1022,1102,1112,1121,
%T A207671 1201,1211,1222,2011,2012,2102,2111,2122,2201,2212,2221,10012,10022,
%U A207671 10102,10111,10121,10202,11002,11021,11101,11111,11122,11222
%N A207671 Numbers in ternary representation that match nonzero polynomials with all coefficients in {0,1,2} that are irreducible modulo 3.
%C A207671 For a discussion and examples in base-10 representation, see A207670.  For the analogous sequence in base 2, see A206073.
%e A207671 (See the Example section of A207669.)
%t A207671 t = Table[IntegerDigits[n, 3], {n, 1, 1000}];
%t A207671 b[n_] := Reverse[Table[x^k, {k, 0, n}]]
%t A207671 p[n_, x_] := t[[n]].b[-1 + Length[t[[n]]]]
%t A207671 Table[p[n, x], {n, 1, 15}]
%t A207671 u = {}; Do[n++;
%t A207671 If[IrreduciblePolynomialQ[p[n, x], Modulus -> 3],
%t A207671   AppendTo[u, n]], {n, 1, 400}]
%t A207671 u                           (* A207669 *)
%t A207671 Complement[Range[200], %]   (* A207670 *)
%t A207671 b[n_] := FromDigits[IntegerDigits[u, 3][[n]]]
%t A207671 Table[b[n], {n, 1, 50}]     (* A207671 *)
%Y A207671 Cf. A207669, A206073.
%K A207671 nonn,base
%O A207671 1,1
%A A207671 _Clark Kimberling_, Feb 26 2012