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%I #14 Feb 18 2019 14:55:29
%S 2158479,2190762,2205528,2219322,2301615,2330397,2336268,2345811,
%T 2358828,2359026,2367609,2388534,2389119,2389638,2397132,2428986,
%U 2504736,2524974,2536152,2583258,2590125,2607222,2620827,2622012,2647866,2649369,2658636,2671593
%N Numbers k such that k^3 contains every digit exactly twice.
%C This sequence has 138 terms.
%H Nathaniel Johnston, <a href="/A154874/b154874.txt">Table of n, a(n) for n = 1..138</a> (full sequence)
%e 2358828^3 = 13124683009764879552, which contains each digit 0..9 exactly twice.
%p lim:=floor((10^20)^(1/3)): for j from ceil((10^19)^(1/3)) to lim do d:=convert(j^3,base,10): doubdig:=true: for k from 0 to 9 do if(numboccur(d,k)<>2)then doubdig:=false:break: fi: od: if(doubdig)then print(j); fi: od: # _Nathaniel Johnston_, May 28 2011
%t With[{cmin=Ceiling[Surd[10^19,3]],cmax=Floor[Surd[10^20,3]]},Select[ Range[ cmin, cmax], Union[ DigitCount[#^3]]=={2}&]] (* _Harvey P. Dale_, Nov 17 2018 *)
%Y Cf. A054038, A074205, A154532, A154566, A154871, A154873.
%K base,easy,fini,full,nonn
%O 1,1
%A _Zhining Yang_, Jan 16 2009