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A207968 Ternary numbers that match irreducible polynomials over {0,1,2}.

%I A207968 #7 Mar 31 2012 12:43:11
%S A207968 10,11,12,20,21,22,101,102,111,112,122,201,202,211,212,221,222,1002,
%T A207968 1011,1021,1022,1101,1102,1112,1121,1201,1202,1211,1222,2001,2011,
%U A207968 2012,2021,2022,2102,2111,2122,2201,2202,2212,2221,10001,10002,10011
%N A207968 Ternary numbers that match irreducible polynomials over {0,1,2}.
%C A207968 These are base 3 representations for the numbers (in base 10) at A207966.
%t A207968 t = Table[IntegerDigits[n, 3], {n, 1, 850}];
%t A207968 b[n_] := Reverse[Table[x^k, {k, 0, n}]]
%t A207968 p[n_, x_] := t[[n]].b[-1 + Length[t[[n]]]]
%t A207968 Table[p[n, x], {n, 1, 15}]
%t A207968 u = {}; Do[n++; If[IrreduciblePolynomialQ[p[n, x]],
%t A207968   AppendTo[u, n]], {n, 300}]; u  (* A207966 *)
%t A207968 Complement[Range[200], u]        (* A207967 *)
%t A207968 b[n_] := FromDigits[IntegerDigits[u, 3][[n]]]
%t A207968 Table[b[n], {n, 1, 50}]          (* A207968 *)
%Y A207968 Cf. A207966, A207966, A206073 (base 2).
%K A207968 nonn
%O A207968 1,1
%A A207968 _Clark Kimberling_, Feb 21 2012