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 A069624 Number of different values taken by the integer part of n^(1/k) for all k > 1. 2
 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 LINKS EXAMPLE a(28) = 4, floor[28^(1/2)] = 5, floor[28^1/3] = 3, floor[28^1/4] = 2, floor [28^1/5] = 1= floor[28^1/k, (k > 5)], etc. The distinct values are 1,2,3 and 5. MAPLE A069624 := proc(n)     local s, k, a ;     s := {} ;     for k from 2 do         a := floor(n^(1/k)) ;         s := s union {a} ;         if a = 1 then             break;         end if;     end do:     nops(s) ; end proc: # R. J. Mathar, May 19 2014 MATHEMATICA f[n_] := Block[{k = 1}, While[ Floor[n^(1/k)] != 1, k++ ]; k]; Table[ Length[ Union[ Table[ Floor[n^(1/k)], {k, 2, f[n]+1}]]], {n, 1, 105}] CROSSREFS Cf. A071913. Sequence in context: A186313 A165020 A235224 * A092139 A084558 A320065 Adjacent sequences:  A069621 A069622 A069623 * A069625 A069626 A069627 KEYWORD nonn AUTHOR Amarnath Murthy, Mar 27 2002 EXTENSIONS Edited by N. J. A. Sloane and Robert G. Wilson v, Jun 14 2002 Definition corrected by Robert Israel, May 18 2014 STATUS approved

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Last modified August 22 21:40 EDT 2019. Contains 326209 sequences. (Running on oeis4.)