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 A131930 #9 Mar 03 2025 14:46:03 %S A131930 2,3,5,7,11,12,13,15,17,19,20,22,23,24,25,26,28,29,30,31,32,33,35,36, %T A131930 37,39,41,42,43,45,47,50,52,53,55,59,61,62,63,65,67,70,71,72,73,75,77, %U A131930 79,82,83,85,89,92,93,95,97,101,102,103,105,107,109,110,112,113,115,120 %N A131930 Numbers k such that the decimal representation of k contains at least one prime factor of k. %C A131930 Numbers k such that A131929(k) > 0; complement of A050695 including 1. %C A131930 All primes are terms. %H A131930 James C. McMahon, <a href="/A131930/b131930.txt">Table of n, a(n) for n = 1..10000</a> %e A131930 55 is a term because 5 | 55. %t A131930 Select[Range[2,120],ContainsAny[Rest[FromDigits/@Subsets[IntegerDigits[#]]],First/@FactorInteger[#]]&] (* _James C. McMahon_, Mar 02 2025 *) %Y A131930 Cf. A131929, A050695. %K A131930 nonn,base %O A131930 1,1 %A A131930 _Reinhard Zumkeller_, Jul 30 2007