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A097449 If n is a cube, replace it with the cube root of n. 1

%I

%S 0,1,2,3,4,5,6,7,2,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,

%T 26,3,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,

%U 49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,4,65,66,67,68,69,70,71,72,73,74

%N If n is a cube, replace it with the cube root of n.

%e The 9th integer is 8 so a(9) = 8^(1/3) = 2.

%t rcr[n_]:=Module[{crn=Power[n, (3)^-1]},If[IntegerQ[crn],crn,n]]; Array[ rcr,80,0] (* _Harvey P. Dale_, Jan 28 2012 *)

%o (PARI) replcube(n) = { for(x=0,n, if(iscube(x),y=x^(1/3),y=x); print1(floor(y)",")) } iscube(n) = { local(r); r = n^(1/3); if(floor(r+.5)^3== n,1,0) }

%o (PARI) a(n)=ispower(n,3,&n);n \\ _Charles R Greathouse IV_, Oct 27 2011

%K nonn,easy

%O 0,3

%A _Cino Hilliard_, Aug 23 2004

%E Corrected by _T. D. Noe_, Oct 25 2006

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Last modified June 18 01:16 EDT 2021. Contains 345098 sequences. (Running on oeis4.)