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 A115554 #6 Jul 15 2021 09:11:53 %S A115554 14287,28574,15384615384615386,23076923076923079,30769230769230772, %T A115554 14285714285714285714285714285714285714285714287, %U A115554 28571428571428571428571428571428571428571428574 %N A115554 Numbers k such that k^2 is the concatenation of two numbers m and 9*m. %e A115554 14287^2 = 2041_18369. %Y A115554 Cf. A102567, A106497, A115527 - A115556. %K A115554 nonn,base %O A115554 1,1 %A A115554 _Giovanni Resta_, Jan 25 2006