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 A351310 #24 Jul 19 2025 11:57:23 %S A351310 1,1,1,1025,1,1,1,1025,59050,1,1,1025,1,1,1,1049601,1,59050,1,1025,1, %T A351310 1,1,1025,9765626,1,59050,1025,1,1,1,1049601,1,1,1,60526250,1,1,1, %U A351310 1025,1,1,1,1025,59050,1,1,1049601,282475250,9765626,1,1025,1,59050,1,1025,1,1 %N A351310 Sum of the 5th powers of the square divisors of n. %C A351310 Inverse Möbius transform of n^5 * c(n), where c(n) is the characteristic function of squares (A010052). - _Wesley Ivan Hurt_, Jun 21 2024 %H A351310 Michael De Vlieger, <a href="/A351310/b351310.txt">Table of n, a(n) for n = 1..10000</a> %F A351310 a(n) = Sum_{d^2|n} (d^2)^5. %F A351310 Multiplicative with a(p) = (p^(10*(1+floor(e/2))) - 1)/(p^10 - 1). - _Amiram Eldar_, Feb 07 2022 %F A351310 From _Amiram Eldar_, Sep 20 2023: (Start) %F A351310 Dirichlet g.f.: zeta(s) * zeta(2*s-10). %F A351310 Sum_{k=1..n} a(k) ~ (zeta(11/2)/11) * n^(11/2). (End) %F A351310 a(n) = Sum_{d|n} d^5 * c(d), where c = A010052. - _Wesley Ivan Hurt_, Jun 21 2024 %F A351310 a(n) = Sum_{d|n} lambda(d)*d^5*sigma_5(n/d), where lambda = A008836. - _Ridouane Oudra_, Jul 19 2025 %e A351310 a(16) = 1049601; a(16) = Sum_{d^2|16} (d^2)^5 = (1^2)^5 + (2^2)^5 + (4^2)^5 = 1049601. %t A351310 f[p_, e_] := (p^(10*(1 + Floor[e/2])) - 1)/(p^10 - 1); a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* _Amiram Eldar_, Feb 07 2022 *) %Y A351310 Sum of the k-th powers of the square divisors of n for k=0..10: A046951 (k=0), A035316 (k=1), A351307 (k=2), A351308 (k=3), A351309 (k=4), this sequence (k=5), A351311 (k=6), A351313 (k=7), A351314 (k=8), A351315 (k=9), A351315 (k=10). %Y A351310 Cf. A010052, A008836, A001160. %K A351310 nonn,easy,mult %O A351310 1,4 %A A351310 _Wesley Ivan Hurt_, Feb 06 2022