A192525 Monotonic ordering of set S generated by these rules: if x and y are in S then 2xy-x-y is in S, and 3 is in S.

3, 12, 57, 264, 282, 1299, 1317, 1407, 6060, 6384, 6474, 6492, 6582, 7032, 29775, 29865, 30279, 30297, 31809, 31917, 32349, 32367, 32457, 32907, 35157, 138864, 139368, 146730, 146820, 148350, 148764, 148872, 148890, 149304, 149322, 151374

Offset

1,1

Links

Table of n, a(n) for n=1..36.

Mathematica

start = {3}; f[x_, y_] := 2 x*y - x - y
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 = NestList[b, start, 12][[-1]] (* A192525 *)
t/3 (* A192526 *)
Table[t[[i]] - t[[i - 1]], {i, 2, Length[t]}]  (* differences *)

Crossrefs

Cf. A192476.

Sequence in context: A020016 A001277 A334773 * A106570 A027140 A110309

Adjacent sequences: A192522 A192523 A192524 * A192526 A192527 A192528

Keyword

nonn

Author

Clark Kimberling, Jul 03 2011

Status

approved