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 A116351 #11 Jul 18 2021 06:47:23 %S A116351 8446,8811,69125298546226023972,69855225553525294045, %T A116351 74604750601020544520,75334677608319814593,92496418993920707747, %U A116351 93226346001219977820,97975871048715228295,98705798056014498368 %N A116351 Numbers k such that k*(k+5) gives the concatenation of two numbers m and m+9. %e A116351 8811 * 8816 = 7767//7776, where // denotes concatenation. %Y A116351 Cf. A028557, A116180, A116338, A116350, A116352. %K A116351 nonn,base %O A116351 1,1 %A A116351 _Giovanni Resta_, Feb 06 2006