A192525 - OEIS

%I #5 Mar 30 2012 18:57:34

%S 3,12,57,264,282,1299,1317,1407,6060,6384,6474,6492,6582,7032,29775,

%T 29865,30279,30297,31809,31917,32349,32367,32457,32907,35157,138864,

%U 139368,146730,146820,148350,148764,148872,148890,149304,149322,151374

%N 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.

%t start = {3}; f[x_, y_] := 2 x*y - x - y

%t b[x_] :=

%t   Block[{w = x},

%t    Select[Union[

%t      Flatten[AppendTo[w,

%t        Table[f[w[[i]], w[[j]]], {i, 1, Length[w]}, {j, 1, i}]]]], # <

%t       500000 &]];

%t t = NestList[b, start, 12][[-1]] (* A192525 *)

%t t/3 (* A192526 *)

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

%Y Cf. A192476.

%K nonn

%O 1,1

%A _Clark Kimberling_, Jul 03 2011