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 A046464 #23 Apr 10 2021 16:59:20 %S A046464 8,17,25,41,47,55,56,63,77,94,101,103,107 %N A046464 Numbers k such that the concatenation of numbers from 1 to k is the product of 5 primes (not necessarily distinct). %H A046464 Patrick De Geest, <a href="http://www.worldofnumbers.com/factorlist.htm">Normal Smarandache Concatenated Numbers, Prime factors from 1 up to n</a> %H A046464 M. Fleuren, <a href="http://www.gallup.unm.edu/~smarandache/michafleuren.htm">Factors and primes of Smarandache sequences</a>. %H A046464 M. Fleuren, <a href="http://www.gallup.unm.edu/~smarandache/micha.txt">Smarandache Factors and Reverse factors</a> %H A046464 Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_008.htm">Puzzle 8. Primes by Listing</a>, The Prime Puzzles & Problems Connection. %t A046464 Select[Range[100],PrimeOmega@FromDigits@Flatten@ IntegerDigits@ Range@# == 5 &] (* _Robert Price_, Oct 11 2019 *) %Y A046464 Cf. A007908, A046460, A050682. %K A046464 nonn,base,hard,more %O A046464 1,1 %A A046464 _Patrick De Geest_, Aug 15 1998 %E A046464 a(9)-a(13) from _Sean A. Irvine_, Apr 10 2021