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 A201020 #10 May 30 2015 08:35:23 %S A201020 6,16,28,32,44,48,68,74,82,84,86,116,123,128,132,144,147,148,161,168, %T A201020 174,182,184,186,213,218,224,228,231,238,242,244,246,264,267,272,276, %U A201020 282,288,289,298,312,321,328,344,368,374,377,378,382,386,387,414,417,418,422 %N A201020 Composite numbers whose multiplicative digital root is 6. %C A201020 Complement of A201019 with respect to A034053. %H A201020 Harvey P. Dale, <a href="/A201020/b201020.txt">Table of n, a(n) for n = 1..1000</a> %e A201020 Number 128 is in sequence because 1*2*8=16, 1*6=6. %t A201020 mdr6Q[n_]:=CompositeQ[n]&&NestWhile[Times@@IntegerDigits[#]&,n,#>9&] ==6; Select[Range[500],mdr6Q] (* _Harvey P. Dale_, May 30 2015 *) %Y A201020 Cf. A201019 (primes whose multiplicative digital root is 6), A034053 (numbers whose multiplicative digital root is 6). %K A201020 nonn,base %O A201020 1,1 %A A201020 _Jaroslav Krizek_, Nov 25 2011