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%I #27 Mar 28 2024 09:03:16
%S 24,48,72,120,144,168,168,192,264,240,264,336,312,408,360,384,456,432,
%T 672,480,504,576,600,744,600,720,648,744,840,720,744,840,912,984,840,
%U 864,888,912,1296,1104,984,1080,1032,1272,1176,1104,1368,1152,1488,1320,1224,1320,1344,1824,1320
%N Sum of the divisors of 24*n - 1.
%C All terms are multiples of 24 [Gupta, Sierpinski]. - Vincenzo Librandi, Apr 07 2011
%C Note that 24n - 1 is also the denominator of the Bruinier-Ono finite algebraic formula for the number of partitions of n (Cf. A183010).
%H Hansraj Gupta, <a href="http://www.ams.org/mathscinet-getitem?mr=14365">Congruent properties of sigma(n)</a>, Math. Student 13 (1945), 25-29.
%H Wacław Sierpiński, <a href="http://pldml.icm.edu.pl/pldml/element/bwmeta1.element.dl-catalog-556369c7-b6cc-4a5b-be36-bfc8e0ca7cfa">Elementary Theory of numbers</a>, Monografie Mathematyczne, Vol. 42 (1964), chapter 4, p. 168.
%F a(n) = A000203(A183010(n)).
%F Sum_{k=1..n} a(k) = c * n^2 + O(n*log(n)), where c = 4*Pi^2/3 = 13.159472... . - _Amiram Eldar_, Mar 28 2024
%e For n = 5 we have that 24*5 - 1 = 119, and the sum of the divisors of 119 is 1 + 7 + 17 + 119 = 144, so a(5) = 144.
%t DivisorSigma[1,24*Range[60]-1] (* _Harvey P. Dale_, Jan 25 2024 *)
%Y Cf. A000203, A008606, A183010, A280098.
%K nonn,easy
%O 1,1
%A _Omar E. Pol_, Dec 25 2016
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