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 A154874 Numbers k such that k^3 contains every digit exactly twice. 3
 2158479, 2190762, 2205528, 2219322, 2301615, 2330397, 2336268, 2345811, 2358828, 2359026, 2367609, 2388534, 2389119, 2389638, 2397132, 2428986, 2504736, 2524974, 2536152, 2583258, 2590125, 2607222, 2620827, 2622012, 2647866, 2649369, 2658636, 2671593 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This sequence has 138 terms. LINKS Nathaniel Johnston, Table of n, a(n) for n = 1..138 (full sequence) EXAMPLE 2358828^3 = 13124683009764879552, which contains each digit 0..9 exactly twice. MAPLE 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 MATHEMATICA 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 *) CROSSREFS Cf. A054038, A074205, A154532, A154566, A154871, A154873. Sequence in context: A253959 A253966 A253762 * A258421 A166930 A183754 Adjacent sequences:  A154871 A154872 A154873 * A154875 A154876 A154877 KEYWORD base,easy,fini,full,nonn AUTHOR Zhining Yang, Jan 16 2009 STATUS approved

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Last modified August 11 09:30 EDT 2020. Contains 336423 sequences. (Running on oeis4.)