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%I #16 Dec 16 2022 09:04:29
%S 15,31,60,63,90,124,120,127,195,186,180,252,210,248,360,255,270,403,
%T 300,378,480,372,360,508,465,434,600,504,450,744,480,511,720,558,720,
%U 819,570,620,840,762,630,992,660,756,1170,744,720,1020,855,961
%N a(n) = sigma(8*n).
%H Seiichi Manyama, <a href="/A283122/b283122.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A000203(8*n).
%F Sum_{k=1..n} a(k) = (23*Pi^2/24) * n^2 + O(n*log(n)). - _Amiram Eldar_, Dec 16 2022
%t Table[DivisorSigma[1, 8 n], {n, 50}] (* _Michael De Vlieger_, Mar 01 2017 *)
%o (PARI) a(n) = sigma(8*n) \\ _Amiram Eldar_, Dec 16 2022
%Y Sigma(k*n): A000203 (k=1), A062731 (k=2), A144613 (k=3), A193553 (k=4), A283118 (k=5), A224613 (k=6), A283078 (k=7), this sequence (k=8), A283123 (k=9).
%Y Cf. A008590.
%K nonn
%O 1,1
%A _Seiichi Manyama_, Mar 01 2017
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