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A192523 Monotonic ordering of set S generated by these rules:  if x and y are in S then 2xy-x-y is in S, and 2 is in S. 3
2, 4, 10, 24, 28, 66, 70, 82, 164, 180, 192, 196, 208, 244, 446, 458, 486, 490, 522, 538, 570, 574, 586, 622, 730, 1104, 1144, 1244, 1256, 1292, 1320, 1336, 1340, 1368, 1372, 1452, 1456, 1468, 1512, 1548, 1564, 1612, 1704, 1708, 1720, 1756, 1864 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..47.

MATHEMATICA

start = {2}; 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}]]]], # <

      5000 &]];

t = NestList[b, start, 10][[-1]] (* A192523 *)

t/2 (* A192524 *)

Table[t[[i]] - t[[i - 1]], {i, 2, Length[t]}]  (* differences *)

CROSSREFS

Cf. A192476.

Sequence in context: A130967 A148087 A156806 * A065832 A072753 A009884

Adjacent sequences:  A192520 A192521 A192522 * A192524 A192525 A192526

KEYWORD

nonn

AUTHOR

Clark Kimberling, Jul 03 2011

STATUS

approved

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Last modified September 28 10:48 EDT 2021. Contains 347714 sequences. (Running on oeis4.)