This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A131760 #8 Dec 21 2015 10:01:03 %S A131760 1,4,9,121,484,676,2178,8712,10000,10201,12321,14641,40000,40804, %T A131760 44944,69696,90000,94249,698896,1002001,1210000,1234321,4008004, %U A131760 4840000,5221225,6760000,6948496,21780000,87120000,100000000,100020001 %N A131760 Numbers n such that n multiplied by its reverse yields a fourth power. %C A131760 This sequence contains palindromic squares and palindromic squares with trailing zeros. Are 2178 and 8721 the only non-palindromic reversible pair in this sequence without trailing zeros? %H A131760 Chai Wah Wu, <a href="/A131760/b131760.txt">Table of n, a(n) for n = 1..108</a> %e A131760 2178 = 2*9*121 and 8712 = 8*9*121, 2718*8712 = (2*3*11)^4. %t A131760 Select[Range[1000000], IntegerQ[(#*FromDigits[Reverse[IntegerDigits[ # ]]])^(1/4)] &] %Y A131760 Cf. A002779 = Palindromic squares. %K A131760 nonn,base %O A131760 1,2 %A A131760 _Tanya Khovanova_, Sep 17 2007 %E A131760 a(20)-a(31) from _Donovan Johnson_, Oct 27 2008