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 A259047 #17 May 31 2024 22:04:19 %S A259047 28749,21757820799,4373079629403 %N A259047 Composite numbers which divide the concatenation of their prime factors, with multiplicity, in ascending order. %C A259047 a(2) found by _Jens Kruse Andersen_, who also cleverly derived 119 large terms of the sequence from the factorization of numbers of the form 10^k+1 (see Links). %C A259047 10^13 < a(4) <= 7810053011863508278028459 (the smallest of J. K. Andersen's large terms). %H A259047 Michael S. Branicky, <a href="/A259047/a259047.txt">Python program for Andersen's algorithm extended to arbitrary base/ordering</a>. %H A259047 Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_472.htm">Puzzle 472. What is the second solution?</a>, The Prime Puzzles & Problems Connection. %H A259047 StackExchange, <a href="http://math.stackexchange.com/questions/1166424/numbers-divide-its-prime-factors-concatenation">New term in ascending order</a>. %e A259047 4373079629403 is equal to 3*367*2713*1464031 and it is a divisor of 336727131464031, hence it is in the sequence. %Y A259047 Cf. A248915. %K A259047 nonn,more,base,hard,bref %O A259047 1,1 %A A259047 _Giovanni Resta_, Jun 17 2015