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Numbers whose biquadrates (fourth powers) are exclusionary.
1

%I #9 Aug 21 2013 18:33:17

%S 2,3,4,7,8,9,24,27,28,32,42,52,53,58,59,67,89,93,203,258,284,324,329,

%T 832,843,2673

%N Numbers whose biquadrates (fourth powers) are exclusionary.

%C The number m with no repeated digits has an exclusionary fourth power m^4 if the latter is made up of digits not appearing in m. Is a subsequence of A111116. Conjectured to be complete. For the corresponding exclusionary biquadrates m^4, see A113317.

%D H. Ibstedt, Solution to Problem 2623, "Exclusionary Powers", pp. 346-9, Journal of Recreational Mathematics, Vol. 32 No.4 2003-4 Baywood NY.

%t ebQ[n_]:=Max[DigitCount[n]]==1&&Intersection[IntegerDigits[n], IntegerDigits[ n^4]]=={}; Select[Range[3000],ebQ] (* _Harvey P. Dale_, Aug 21 2013 *)

%K base,nonn,fini

%O 1,1

%A _Lekraj Beedassy_, Oct 26 2005