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A070279 Sum of digits of n equals the sum of digits of 2n. 6

%I #15 Nov 21 2013 12:47:47

%S 9,18,27,36,45,54,63,72,81,90,99,108,117,126,135,153,162,171,180,189,

%T 198,207,216,225,252,261,270,279,288,297,306,315,351,360,369,378,387,

%U 396,405,450,459,468,477,486,495,504,513,522,531,540,549,594,603,612

%N Sum of digits of n equals the sum of digits of 2n.

%C 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 Charles R Greathouse IV, <a href="/A070279/b070279.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Range[1000],Total[IntegerDigits[#]]==Total[IntegerDigits[ 2#]]&] (* _Harvey P. Dale_, Jul 22 2011 *)

%o (PARI) is(n)=sumdigits(n)==sumdigits(2*n) \\ _Charles R Greathouse IV_, Jun 17 2012

%K easy,nonn,base

%O 1,1

%A _Benoit Cloitre_, May 09 2002

%E Incorrect comment removed by _Charles R Greathouse IV_, Jun 17 2012

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Last modified April 23 02:53 EDT 2024. Contains 371906 sequences. (Running on oeis4.)