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 A116302 #7 Jul 18 2021 02:55:19 %S A116302 27,71,79822844,69852478553064869297984899963806, %T A116302 77473062193002372448027740546438,77747359197583788609974143907618, %U A116302 84341826458653210947638195982114,85367942837521291760016984490250 %N A116302 Numbers k such that k*(k+3) gives the concatenation of two numbers m and m+2. %e A116302 79822844 * 79822847 = 63716866//63716868, where // denotes concatenation. %Y A116302 Cf. A116171, A116296, A116301, A116303, A116309. %K A116302 nonn,base %O A116302 1,1 %A A116302 _Giovanni Resta_, Feb 06 2006