OFFSET
1,1
COMMENTS
See A192476.
MATHEMATICA
start = {2}; f[x_, y_] := (x + 1) (y + 1)
b[z_] :=
Block[{w = z},
Select[Union[
Flatten[AppendTo[w,
Table[f[w[[i]], w[[j]]], {i, 1, Length[w]}, {j, 1, i}]]]], # <
30000 &]];
t = NestList[b, start, 10][[-1]] (* A192518 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Jul 03 2011
STATUS
approved