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 A088799 #5 Jun 08 2025 16:15:42 %S A088799 3,11,9491,12258083,36774249,2159487563,2561252691,2723957777, %T A088799 6478462689,8171873331,333351714587,146217070005379,438651210016137, %U A088799 13919982618156833,41759947854470499,1278907806311980217974478364841 %N A088799 Numbers n which are divisors of the number formed by concatenating (n-3), (n-2) and (n-1) in that order. %C A088799 Apart from 11, each other term in this sequence appears to also be a factor of the number formed by concatenating (n+3), (n+2) and (n+1) in that order. All terms appear to be prime. When evaluating concat((n+3),(n+2),(n+1)) - concat((n-3),(n-2),(n-1)) for members larger than 11 the difference appears to always be a number of the form 6(0)...4(0)...2 with the same number of zeros on both sides of the 4. The member will be a prime factor of this number. By factoring numbers of the form 6(0)...4(0)...2 and testing the results, three further members of this sequence have been found: 2723957777, 1260049494294190236301929754269107568067 and 103945392111236434211250670719387720140245499. I have not included these in the list of members above as they were not arrived at through brute force as the first 4 terms were and there may be other intervening terms. %e A088799 a(3)=9491 because 9491 is a factor of 948894899490. %Y A088799 Cf. A069860, A088797, A088798. %K A088799 base,nonn %O A088799 1,1 %A A088799 _Chuck Seggelin_, Oct 19 2003 %E A088799 More terms from _David Wasserman_, Aug 25 2005