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A207968 Ternary numbers that match irreducible polynomials over {0,1,2}. 3

%I

%S 10,11,12,20,21,22,101,102,111,112,122,201,202,211,212,221,222,1002,

%T 1011,1021,1022,1101,1102,1112,1121,1201,1202,1211,1222,2001,2011,

%U 2012,2021,2022,2102,2111,2122,2201,2202,2212,2221,10001,10002,10011

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

%C These are base 3 representations for the numbers (in base 10) at A207966.

%t t = Table[IntegerDigits[n, 3], {n, 1, 850}];

%t b[n_] := Reverse[Table[x^k, {k, 0, n}]]

%t p[n_, x_] := t[[n]].b[-1 + Length[t[[n]]]]

%t Table[p[n, x], {n, 1, 15}]

%t u = {}; Do[n++; If[IrreduciblePolynomialQ[p[n, x]],

%t AppendTo[u, n]], {n, 300}]; u (* A207966 *)

%t Complement[Range[200], u] (* A207967 *)

%t b[n_] := FromDigits[IntegerDigits[u, 3][[n]]]

%t Table[b[n], {n, 1, 50}] (* A207968 *)

%Y Cf. A207966, A207966, A206073 (base 2).

%K nonn

%O 1,1

%A _Clark Kimberling_, Feb 21 2012

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Last modified January 19 17:26 EST 2022. Contains 350466 sequences. (Running on oeis4.)