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 A116124 #8 Jul 20 2021 23:42:32 %S A116124 61,65479,84289,106609,225649,275599,453589,1869505,2272555,2738291, %T A116124 3221951,1667833021,2475062749,2525062249,3500010739,9032526511, %U A116124 9225507211,1753016898055,1860598847399,3233666953849,3379207972471 %N A116124 Numbers k such that k concatenated with k-5 gives the product of two numbers which differ by 5. %e A116124 9225507211//9225507206 = 9604950394 * 9604950399, where // denotes concatenation. %Y A116124 Cf. A116118, A054214, A116125, A116130, A116255. %K A116124 nonn,base %O A116124 1,1 %A A116124 _Giovanni Resta_, Feb 06 2006