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A207967 Numbers that match non-irreducible polynomials over {0,1,2}; complement of A207966.

%I A207967 #5 Mar 30 2012 18:58:13
%S A207967 1,2,9,12,15,16,18,21,24,27,28,30,32,33,36,39,40,42,44,45,48,50,51,52,
%T A207967 54,56,57,60,63,64,66,68,69,70,72,75,76,78,80,81,84,87,88,90,91,93,96,
%U A207967 99,100,102,104,105,108,111,112,114,116,117,119,120,123,124
%N A207967 Numbers that match non-irreducible polynomials over {0,1,2}; complement of A207966.
%C A207967 See A207966.
%e A207967 (See A207966.)
%t A207967 t = Table[IntegerDigits[n, 3], {n, 1, 850}];
%t A207967 b[n_] := Reverse[Table[x^k, {k, 0, n}]]
%t A207967 p[n_, x_] := t[[n]].b[-1 + Length[t[[n]]]]
%t A207967 Table[p[n, x], {n, 1, 15}]
%t A207967 u = {}; Do[n++; If[IrreduciblePolynomialQ[p[n, x]],
%t A207967   AppendTo[u, n]], {n, 300}]; u  (* A207966 *)
%t A207967 Complement[Range[200], u]        (* A207967 *)
%t A207967 b[n_] := FromDigits[IntegerDigits[u, 3][[n]]]
%t A207967 Table[b[n], {n, 1, 50}]          (* A207968 *)
%Y A207967 Cf. A207966, A207968.
%K A207967 nonn
%O A207967 1,2
%A A207967 _Clark Kimberling_, Feb 21 2012