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 A070279 #15 Nov 21 2013 12:47:47 %S A070279 9,18,27,36,45,54,63,72,81,90,99,108,117,126,135,153,162,171,180,189, %T A070279 198,207,216,225,252,261,270,279,288,297,306,315,351,360,369,378,387, %U A070279 396,405,450,459,468,477,486,495,504,513,522,531,540,549,594,603,612 %N A070279 Sum of digits of n equals the sum of digits of 2n. %C A070279 A010888(a(n)) = 9, but not all multiples of 9 belong to the sequence: e.g. 144=16*9: A007953(144)=1+4+4=9, but A007953(144*2)=A007953(288)=2+8+8=18. - _Reinhard Zumkeller_, May 15 2002 %H A070279 Charles R Greathouse IV, <a href="/A070279/b070279.txt">Table of n, a(n) for n = 1..10000</a> %t A070279 Select[Range[1000],Total[IntegerDigits[#]]==Total[IntegerDigits[ 2#]]&] (* _Harvey P. Dale_, Jul 22 2011 *) %o A070279 (PARI) is(n)=sumdigits(n)==sumdigits(2*n) \\ _Charles R Greathouse IV_, Jun 17 2012 %K A070279 easy,nonn,base %O A070279 1,1 %A A070279 _Benoit Cloitre_, May 09 2002 %E A070279 Incorrect comment removed by _Charles R Greathouse IV_, Jun 17 2012