A192647 Monotonic ordering of set S generated by these rules: if x and y are in S and x^2 - y^2 > 0 then x^2 - y^2 is in S, and 1 and 3 are in S.

1, 3, 8, 55, 63, 944, 2961, 3016, 3024, 3905, 3960, 3968, 48320, 63424, 328735, 377055, 432575, 495999, 887167, 888111, 891072, 891127, 891135, 6104449, 6152769, 6481504, 6537024, 6585344, 6600448, 6648768, 6914079, 6977503, 7876385, 8205120

Offset

1,2

Comments

See A192645.

Links

Ivan Neretin, Table of n, a(n) for n = 1..10000

Mathematica

start = {1, 3};
f[x_, y_] := If[MemberQ[Range[1, 500000], x^2 - y^2], x^2 - y^2]
b[x_] :=
  Block[{w = x},
   Select[Union[
     Flatten[AppendTo[w,
       Table[f[w[[i]], w[[j]]], {i, 1, Length[w]}, {j, 1, i}]]]], # <
      500000 &]];
t = FixedPoint[b, start]  (* A192647 *)

Crossrefs

Cf. A192476, A192646.

Sequence in context: A026088 A354851 A322461 * A121567 A222788 A308572

Adjacent sequences: A192644 A192645 A192646 * A192648 A192649 A192650

Keyword

nonn

Author

Clark Kimberling, Jul 06 2011

Status

approved