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A207968 Ternary numbers that match irreducible polynomials over {0,1,2}. 3
10, 11, 12, 20, 21, 22, 101, 102, 111, 112, 122, 201, 202, 211, 212, 221, 222, 1002, 1011, 1021, 1022, 1101, 1102, 1112, 1121, 1201, 1202, 1211, 1222, 2001, 2011, 2012, 2021, 2022, 2102, 2111, 2122, 2201, 2202, 2212, 2221, 10001, 10002, 10011 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

LINKS

Table of n, a(n) for n=1..44.

MATHEMATICA

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

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

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

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

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

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

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

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

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

CROSSREFS

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

Sequence in context: A320601 A305130 A098395 * A207671 A154328 A112654

Adjacent sequences:  A207965 A207966 A207967 * A207969 A207970 A207971

KEYWORD

nonn

AUTHOR

Clark Kimberling, Feb 21 2012

STATUS

approved

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Last modified November 28 10:05 EST 2021. Contains 349401 sequences. (Running on oeis4.)