A196244 Number of distinct values taken by r^r^...^r where r=1/2 (with n r's and parentheses inserted in all possible ways).
1, 1, 2, 4, 9, 20, 47, 111, 271, 670, 1685, 4295, 11074, 28824
Offset: 1
Programs
-
Mathematica
f[1] = {1/2}; f[n_] := f[n] = Union[Flatten[Table[Outer[Power, f[k], f[n - k]], {k, n - 1}]], SameTest -> Equal]; Table[Length[f[n]], {n, 1, 10}] (* Vladimir Reshetnikov, Nov 01 2011 *)
Extensions
a(13)-a(14) from Alois P. Heinz, Feb 20 2013