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A239588 Fourth powers that are cyclops numbers.

%I A239588 #13 Dec 20 2015 19:50:21
%S A239588 0,7890481,9150625,623201296,981506241,17363069361,18945044881,
%T A239588 28813025536,33871089681,38167092496,45954068161,89526025681,
%U A239588 95565066496,1421970391296,1551160647936,1736870953216,3941340648961,4771970346256,5281980641536,5436960129441
%N A239588 Fourth powers that are cyclops numbers.
%C A239588 Intersection of A000583 (Fourth powers) and A134808 (Cyclops numbers).
%H A239588 Colin Barker, <a href="/A239588/b239588.txt">Table of n, a(n) for n = 1..1500</a>
%F A239588 a(n) = A239591(n)^4.
%t A239588 cn4Q[n_]:=Module[{idn=IntegerDigits[n],len},len=Length[idn]; OddQ[ len] && idn[[(len+1)/2]]==0&&DigitCount[n,10,0]==1]; Select[Range[0,2000]^4, cn4Q] (* _Harvey P. Dale_, Dec 20 2015 *)
%o A239588 (PARI)
%o A239588 is_cyclops(k) = {
%o A239588   if(k==0, return(1));
%o A239588   my(d=digits(k), j);
%o A239588   if(#d%2==0 || d[#d\2+1]!=0, return(0));
%o A239588   for(j=1, #d\2, if(d[j]==0, return(0)));
%o A239588   for(j=#d\2+2, #d, if(d[j]==0, return(0)));
%o A239588   return(1)}
%o A239588 s=[]; for(n=0, 2000, if(is_cyclops(n^4), s=concat(s, n^4))); s
%Y A239588 Cf. A000583, A134808, A160711, A239587, A239589, A239590, A239591.
%K A239588 nonn,base
%O A239588 1,2
%A A239588 _Colin Barker_, Mar 24 2014