OFFSET
1,1
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
KEYWORD
nonn
AUTHOR
Clark Kimberling, Jul 03 2011
STATUS
approved