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 A115429 #8 Jul 15 2021 06:19:43 %S A115429 6001,6433,11085116,44496481,96040393,115916930617,227007035017, %T A115429 274101929528,434985419768,749978863753,996004003993,1365379857457948, %U A115429 1410590590957816,1762388551055953,2307340946901148,2700383162251217 %N A115429 Numbers k such that the concatenation of k with k+8 gives a square. %C A115429 Also numbers k such that k concatenated with k+7 gives the product of two numbers which differ by 2. %C A115429 Also numbers k such that k concatenated with k+4 gives the product of two numbers which differ by 4. %C A115429 Also numbers k such that k concatenated with k-1 gives the product of two numbers which differ by 6. %C A115429 Also numbers k such that k concatenated with k-8 gives the product of two numbers which differ by 8. %e A115429 6001//6009 = 7747^2, where // denotes concatenation. %e A115429 96040393//96040400 = 98000200 * 98000202. %e A115429 96040393//96040397 = 98000199 * 98000203. %e A115429 96040393//96040392 = 98000198 * 98000204. %Y A115429 Cf. A030465, A102567, A115426, A115437, A115428, A115430, A115431, A115432, A115433, A115434, A115435, A115436, A115440. %Y A115429 Cf. A116107, A116109, A116113, A116239. %Y A115429 Cf. A116205, A115430, A116335, A116185, A116187, A116317. %Y A115429 Cf. A116131, A116112, A116152, A116159, A116282. %K A115429 base,nonn %O A115429 1,1 %A A115429 _Giovanni Resta_, Jan 24 2006 %E A115429 Edited by _N. J. A. Sloane_, Apr 15 2007