login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A188065 Numbers n such that n^3 contains the same digits as some other cube. 1
5, 8, 35, 38, 50, 80, 101, 102, 110, 178, 196, 201, 221, 227, 257, 258, 279, 289, 319, 329, 331, 341, 345, 350, 355, 356, 371, 379, 380, 384, 405, 406, 408, 417, 427, 455, 457, 473, 497, 500, 514, 553, 564, 576, 635, 638, 639, 641, 644, 656, 665, 668, 674, 689, 709, 711, 722, 725, 773, 781, 792, 800, 804, 836, 858, 862, 894, 923, 933, 943, 961, 973, 978, 981, 983, 992, 996 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

5 is a member since 5^3 = 125, and 512 = 8^3.

178^3 = 5639752 has same digits as 196^3 = 7529536, so 178 and 196 are in the sequence

MAPLE

dmax:= 10: # to get all terms of at most dmax digits.

N:= 'N':

S:= {}:

for n from 1 while n^3 < 10^dmax do

  w:= sort(convert(n^3, base, 10));

  if assigned(N[w]) then

    if N[w] = 0 then S:= S union {n}

    else

      S:= S union {n, N[w]};

      N[w] = 0

    fi

  else N[w]:= n

  fi

od:

sort(convert(S, list)); # Robert Israel, Jun 15 2017

MATHEMATICA

id3Q[n_]:=Module[{idn3=Sort[IntegerDigits[n^3]], perms}, perms= FromDigits/@ Permutations[idn3]; Length[Select[perms, Sort[IntegerDigits[#]]==idn3 && IntegerQ[#^(1/3)]&]]>1]; Select[Range[1000], id3Q] (* Harvey P. Dale, Apr 27 2012 *)

PROG

(PARI) do(n)=my(v=List()); for(D=1, n, my(m=Map(), low=sqrtnint(10^(D-1)-1, 3)+1, high=sqrtnint(10^D-1, 3), n3, d); for(n=low, high, d=vecsort(digits(n3=n^3)); if(mapisdefined(m, d), mapput(m, d, 1), mapput(m, d, 0))); for(n=low, high, if(mapget(m, vecsort(digits(n^3))), listput(v, n)))); Set(v) \\ Charles R Greathouse IV, Jun 15 2017

CROSSREFS

Sequence in context: A275003 A032790 A187997 * A204676 A219947 A075273

Adjacent sequences:  A188062 A188063 A188064 * A188066 A188067 A188068

KEYWORD

nonn,base

AUTHOR

Claudio Meller, Mar 20 2011

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 23 13:57 EST 2022. Contains 350511 sequences. (Running on oeis4.)