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Fourth powers ending in a (different) positive fourth power.
1

%I #20 Jan 27 2021 10:31:46

%S 81,2401,6561,14641,28561,38416,50625,83521,130321,194481,234256,

%T 279841,390625,531441,707281,810000,923521,1185921,1500625,1679616,

%U 1874161,2313441,2825761,3418801,4100625,4879681,5308416,5764801,6765201,7311616

%N Fourth powers ending in a (different) positive fourth power.

%H Harvey P. Dale, <a href="/A038676/b038676.txt">Table of n, a(n) for n = 1..1000</a>

%t ds[n_] := DeleteCases[NestWhileList[FromDigits[Rest[IntegerDigits[#]]] &, n, # > 9 &], 0]; Select[Range[2, 52]^4, Or @@ IntegerQ /@ (Rest[ds[#]]^(1/4)) &] (* _Jayanta Basu_, Jul 10 2013 *)

%t fpQ[n_]:=Module[{idn=IntegerDigits[n]},AnyTrue[Select[Table[Surd[ FromDigits[ Take[ idn,-i]],4],{i,Length[idn]-1}],#>0&],IntegerQ]]; Select[ Range[60]^4,fpQ] (* The program uses the AnyTrue function from Mathematica version 10 *) (* _Harvey P. Dale_, Aug 06 2016 *)

%Y Cf. A000583, A038677.

%K nonn,base,easy

%O 1,1

%A _N. J. A. Sloane_

%E Name clarified by _Sean A. Irvine_, Jan 26 2021