A192646 First differences of A192645.

1, 1, 2, 3, 8, 5, 3, 15, 16, 5, 3, 72, 50, 7, 39, 16, 5, 3, 65, 49, 8, 39, 16, 5, 3, 72, 39, 16, 5, 3, 369, 1, 135, 185, 192, 39, 8, 8, 5, 3, 1, 368, 190, 369, 1, 46, 89, 47, 8, 130, 192, 39, 16, 5, 3, 17, 118, 185, 49, 48, 87, 8, 39, 16, 5, 3, 114, 192, 39, 16, 5, 3, 48

Offset

1,3

Comments

Does this sequence include 1 infinitely many times?

Links

Table of n, a(n) for n=1..73.

Example

A192645 = (1, 2, 3, 5, 8, 16, 21, ...) gives (2-1, 3-2, 5-3, 8-5, 16-8, 21-16, ...)

Mathematica

start = {1, 2};
f[x_, y_] := If[MemberQ[Range[1, 5000], 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}]]]], # <
      5000 &]];
t = FixedPoint[b, start]  (* A192645 *)
Differences[t] (* A192646 *)

Crossrefs

Cf. A192476, A192645.

Sequence in context: A299788 A244915 A244668 * A338841 A100208 A277972

Adjacent sequences: A192643 A192644 A192645 * A192647 A192648 A192649

Keyword

nonn

Author

Clark Kimberling, Jul 06 2011

Status

approved