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 A030686 #12 Apr 01 2020 14:26:50 %S A030686 16,49,900,169,256,361,4900,6400,8100,10000,12100,1444,16900,19600, %T A030686 22500,25600,28900,3249,36100,40000,44100,48400,52900,57600,62500, %U A030686 67600,72900,78400,84100,90000,96100,102400,108900,115600,122500 %N A030686 Smallest nontrivial extension of n^2 which is a square. %C A030686 Nontrivial extension means appending at least one digit even if the number is already a square. %H A030686 M. F. Hasler, <a href="/wiki/M. F. Hasler/Truncated_squares">Truncated squares</a>, OEIS wiki, Jan 16 2012 %H A030686 <a href="/index/Sq#sqtrunc">Index to sequences related to truncating digits of squares</a>. %F A030686 a(n) = A030687(n)^2. - _M. F. Hasler_, Sep 28 2014 %F A030686 a(n) = A030666(n^2). - _Alonso del Arte_, Apr 01 2020 %Y A030686 Cf. A030687, A023110, A031149, A031150, A202303. %Y A030686 See also A023110 = A031149^2 and A202303 = A031150^2 for a related concept, and cross-references there (and in links) for the analog in bases other than 10. - _M. F. Hasler_, Sep 28 2014 %K A030686 nonn,base %O A030686 1,1 %A A030686 _Patrick De Geest_