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 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). 7
 1, 1, 2, 4, 9, 20, 47, 111, 271, 670, 1685, 4295, 11074, 28824 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Table of n, a(n) for n=1..14. 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 *) CROSSREFS Cf. A002845, A082499. Sequence in context: A036618 A349014 A003018 * A035084 A363557 A213905 Adjacent sequences: A196241 A196242 A196243 * A196245 A196246 A196247 KEYWORD nonn,more AUTHOR Vladimir Reshetnikov, Oct 27 2011 EXTENSIONS a(13)-a(14) from Alois P. Heinz, Feb 20 2013 STATUS approved

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Last modified December 3 19:10 EST 2023. Contains 367540 sequences. (Running on oeis4.)