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A155146 Numbers k such that k^3 has exactly 3 different digits.

%I A155146 #31 Jun 30 2025 14:17:17
%S A155146 5,6,8,9,14,15,30,36,40,62,70,92,101,110,173,192,211,300,400,700,888,
%T A155146 1001,1010,1100,1920,3000,3543,4000,7000,8880,10001,10010,10100,11000,
%U A155146 19200,30000,35430,40000,70000,88800,100001,100010,100100,101000,110000,110011
%N A155146 Numbers k such that k^3 has exactly 3 different digits.
%H A155146 Chai Wah Wu, <a href="/A155146/b155146.txt">Table of n, a(n) for n = 1..103</a>
%e A155146 14 is in the list because 14^3 = 2744. - _Jon Perry_, Nov 04 2014
%p A155146 a := proc (n) if nops(convert(convert(n^3, base, 10), set)) = 3 then n else end if end proc: seq(a(n), n = 1 .. 150000); # _Emeric Deutsch_, Jan 27 2009
%t A155146 Select[Range[120000], Length[Union[IntegerDigits[#^3]]]==3&] (* _Vincenzo Librandi_, Nov 04 2014 *)
%o A155146 (Python)
%o A155146 A155146_list, n3, m = [], 0, 0
%o A155146 for n in range(1,10**7):
%o A155146     m += 6*(n-1)
%o A155146     n3 += m + 1
%o A155146     if len(set(str(n3))) == 3:
%o A155146         A155146_list.append(n) # _Chai Wah Wu_, Nov 03 2014
%o A155146 (Magma) [n: n in [0..120000] | #Set(Intseq(n^3)) eq 3]; // _Vincenzo Librandi_, Nov 04 2014
%o A155146 (PARI) is(n)=#Set(digits(n^3))==3 \\ _Charles R Greathouse IV_, Feb 11 2017
%Y A155146 Cf. A030292.
%K A155146 nonn,base
%O A155146 1,1
%A A155146 _Dmitry Kamenetsky_, Jan 21 2009
%E A155146 Extended by _Emeric Deutsch_, Jan 27 2009