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 A115443 #5 Jun 18 2021 18:16:20 %S A115443 81,8157,9801,467347,532654,998001,76450589,99980001,7801738415, %T A115443 8593817623,9208120793,9999800001,346667333467,401461854015, %U A115443 598538145986,653332666534,945207479453,999998000001,48349470735060 %N A115443 Numbers whose square is the concatenation of two numbers k and k-4. %e A115443 9605_9601 = 9801^2. %Y A115443 Cf. A030467, A106497, A115432, A115427, A115438, A115439, A115440, A115441, A115442, A115444, A115445, A115446, A115447. %K A115443 base,nonn %O A115443 1,1 %A A115443 _Giovanni Resta_, Jan 25 2006