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%I #27 Sep 08 2022 08:46:06
%S 135,145,203,221,223,225,227,233,243,244,245,247,249,254,257,265,272,
%T 273,275,276,299,313,327,329,334,338,341,345,347,352,365,366,368,382,
%U 384,388,393,395,398,403,405,409,411,412,434,439,447,452,455,473,486,493
%N Numbers k such that k^3 has one or more occurrences of exactly seven different digits.
%H Colin Barker, <a href="/A235809/b235809.txt">Table of n, a(n) for n = 1..1000</a>
%e 135 is in the sequence because 135^3 = 2460375, which contains exactly seven different digits.
%t Select[Range[500], Length[Union[IntegerDigits[#^3]]]==7&] (* _Vincenzo Librandi_, Nov 07 2014 *)
%o (PARI) s=[]; for(n=1, 600, if(#vecsort(eval(Vec(Str(n^3))),,8)==7, s=concat(s, n))); s
%o (Magma) [n: n in [0..1200] | #Set(Intseq(n^3)) eq 7]; // _Vincenzo Librandi_, Nov 07 2014
%o (PARI) for(n=0,10^3,if(#Set(digits(n^3))==7,print1(n,", "))); \\ _Joerg Arndt_, Nov 10 2014
%o (Python)
%o from itertools import count, islice
%o def A235809gen(): return filter(lambda n:len(set(str(n**3))) == 7,count(0))
%o A235809_list = list(islice(A235809gen(),26)) # _Chai Wah Wu_, Dec 23 2021
%Y Cf. A030292, A155146, A155147, A235807, A235808, A235810, A235811, A119735.
%K nonn,base
%O 1,1
%A _Colin Barker_, Jan 19 2014
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