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Multiples of 24.
27

%I #54 Apr 18 2017 08:54:28

%S 0,24,48,72,96,120,144,168,192,216,240,264,288,312,336,360,384,408,

%T 432,456,480,504,528,552,576,600,624,648,672,696,720,744,768,792,816,

%U 840,864,888,912,936,960,984,1008,1032,1056,1080,1104,1128,1152,1176,1200

%N Multiples of 24.

%C If n is a multiple of 24, also the sum of the divisors of n-1 is a multiple of 24. - _Vincenzo Librandi_, Apr 12 2014

%C This is the sequence of numbers n such that A259748(n)/n = 11/12. - _Danny Rorabaugh_, Oct 22 2015

%H Vincenzo Librandi, <a href="/A008606/b008606.txt">Table of n, a(n) for n = 0..1000</a>

%H Milan Janjic, <a href="http://www.pmfbl.org/janjic/">Enumerative Formulas for Some Functions on Finite Sets</a>

%H Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>

%H INRIA Algorithms Project, <a href="http://ecs.inria.fr/services/structure?nbr=336">Encyclopedia of Combinatorial Structures 336</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2, -1).

%F G.f.: 24*x/(1-x)^2. - _Vincenzo Librandi_, Jun 11 2013

%F a(n) = 24*A001477(n) - _Danny Rorabaugh_, Oct 24 2015

%t Range[0, 1500, 24] (* _Vladimir Joseph Stephan Orlovsky_, Jun 01 2011 *)

%t CoefficientList[Series[24 x / (x - 1)^2, {x, 0, 60}], x] (* _Vincenzo Librandi_, Jun 11 2013 *)

%o (PARI) a(n)=24*n \\ _Charles R Greathouse IV_, Sep 24 2015

%Y Cf. A008604, A008605.

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_.