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A239591 Numbers whose fourth powers are cyclops numbers.

%I A239591 #12 Jun 25 2022 11:58:44
%S A239591 0,53,55,158,177,363,371,412,429,442,463,547,556,1092,1116,1148,1409,
%T A239591 1478,1516,1527,1612,1622,1633,1692,1694,1724,1738,1754,3262,3263,
%U A239591 3276,3283,3338,3362,3366,3402,3436,3464,3468,3473,3512,3538,3631,3723,3724,3833
%N A239591 Numbers whose fourth powers are cyclops numbers.
%H A239591 Colin Barker, <a href="/A239591/b239591.txt">Table of n, a(n) for n = 1..1000</a>
%e A239591 158 is in the sequence because 158^4 = 623201296, which is a cyclops number.
%o A239591 (PARI)
%o A239591 is_cyclops(k) = {
%o A239591   if(k==0, return(1));
%o A239591   my(d=digits(k), j);
%o A239591   if(#d%2==0 || d[#d\2+1]!=0, return(0));
%o A239591   for(j=1, #d\2, if(d[j]==0, return(0)));
%o A239591   for(j=#d\2+2, #d, if(d[j]==0, return(0)));
%o A239591   return(1)}
%o A239591 s=[]; for(n=0, 5000, if(is_cyclops(n^4), s=concat(s, n))); s
%Y A239591 Cf. A000583, A134808, A160711, A239587, A239588, A239589, A239590.
%K A239591 nonn,base
%O A239591 1,2
%A A239591 _Colin Barker_, Mar 24 2014