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 A050676 #25 Oct 01 2023 07:34:35
%S A050676 1,3,2,9,8,11,28,6,26,20
%N A050676 Let b(n) = number of prime factors (with multiplicity) of concatenation of numbers from 1 to n; sequence gives smallest number m with b(m) = n.
%C A050676 a(11) <= 148, a(12) = 104, a(13) = 100, a(14) = 54, a(15) <= 184. - _Michael S. Branicky_, Dec 14 2022 using factorizations at the De Geest link
%H A050676 Patrick De Geest, <a href="http://www.worldofnumbers.com/factorlist.htm">Normal Smarandache Concatenated Numbers, Prime factors from 1 up to n</a>
%H A050676 Micha Fleuren, <a href="http://www.gallup.unm.edu/~smarandache/michafleuren.htm">Factors and primes of Smarandache sequences</a>.
%H A050676 Micha Fleuren, <a href="http://www.gallup.unm.edu/~smarandache/micha.txt">Smarandache Factors and Reverse factors</a>
%H A050676 Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_008.htm">Puzzle 8. Primes by Listing</a>, The Prime Puzzles & Problems connection.
%t A050676 Join[{1},Table[i=1; While[PrimeOmega[FromDigits[Flatten[IntegerDigits[Range[i]]]]]!=n,i++]; i,{n,2,10}]] (* _Jayanta Basu_, May 30 2013 *)
%Y A050676 Cf. A007908, A050678, A046460.
%K A050676 nonn,base,hard,more
%O A050676 1,2
%A A050676 _Patrick De Geest_, Aug 15 1999