OFFSET
1,1
COMMENTS
These are base 3 representations for the numbers (in base 10) at A207966.
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
KEYWORD
nonn
AUTHOR
Clark Kimberling, Feb 21 2012
STATUS
approved