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 A208273 #14 Oct 09 2024 04:36:00 %S A208273 12,20,21,22,24,25,26,27,28,32,42,52,62,72,82,92,102,112,120,121,122, %T A208273 123,124,125,126,128,129,132,142,152,162,172,182,192,200,201,202,203, %U A208273 204,205,206,207,208,209,210,212,213,214,215,216,217,218,219,220,221 %N A208273 Composite numbers containing a digit 2. %C A208273 Subsequence of A011532. Complement of A208272 with respect to A011532. %H A208273 Robert Israel, <a href="/A208273/b208273.txt">Table of n, a(n) for n = 1..10000</a> %p A208273 filter:= proc(n) not isprime(n) and member(2,convert(n,base,10)) end proc: %p A208273 select(filter, [$4..300]); # _Robert Israel_, Oct 09 2024 %t A208273 Select[Range[300], ! PrimeQ[#] && MemberQ[IntegerDigits[#], 2] &] (* _T. D. Noe_, Mar 06 2012 *) %t A208273 Select[Range[300],CompositeQ[#]&&DigitCount[#,10,2]>0&] (* _Harvey P. Dale_, Sep 08 2024 *) %Y A208273 Cf. A208272 (primes containing a digit 2), A011532 (numbers containing a digit 2). %K A208273 nonn,base %O A208273 1,1 %A A208273 _Jaroslav Krizek_, Mar 04 2012