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A351316
Sum of the 10th powers of the square divisors of n.
3
1, 1, 1, 1048577, 1, 1, 1, 1048577, 3486784402, 1, 1, 1048577, 1, 1, 1, 1099512676353, 1, 3486784402, 1, 1048577, 1, 1, 1, 1048577, 95367431640626, 1, 3486784402, 1048577, 1, 1, 1, 1099512676353, 1, 1, 1, 3656161927895954, 1, 1, 1, 1048577, 1, 1, 1, 1048577, 3486784402, 1, 1
OFFSET
1,4
COMMENTS
Inverse Möbius transform of n^10 * c(n), where c(n) is the characteristic function of squares (A010052). - Wesley Ivan Hurt, Jun 21 2024
LINKS
FORMULA
a(n) = Sum_{d^2|n} (d^2)^10.
Multiplicative with a(p) = (p^(20*(1+floor(e/2))) - 1)/(p^20 - 1). - Amiram Eldar, Feb 07 2022
G.f.: Sum_{k>0} k^20*x^(k^2)/(1-x^(k^2)). - Seiichi Manyama, Feb 12 2022
From Amiram Eldar, Sep 20 2023: (Start)
Dirichlet g.f.: zeta(s) * zeta(2*s-20).
Sum_{k=1..n} a(k) ~ (zeta(21/2)/21) * n^(21/2). (End)
a(n) = Sum_{d|n} d^10 * c(d), where c = A010052. - Wesley Ivan Hurt, Jun 21 2024
EXAMPLE
a(16) = 1099512676353; a(16) = Sum_{d^2|16} (d^2)^10 = (1^2)^10 + (2^2)^10 + (4^2)^10 = 1099512676353.
MATHEMATICA
f[p_, e_] := (p^(20*(1 + Floor[e/2])) - 1)/(p^20 - 1); a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100] (* Amiram Eldar, Feb 07 2022 *)
Table[Total[Select[Divisors[n], IntegerQ[Sqrt[#]]&]^10], {n, 50}] (* Harvey P. Dale, Aug 24 2024 *)
PROG
(PARI) my(N=99, x='x+O('x^N)); Vec(sum(k=1, N, k^20*x^k^2/(1-x^k^2))) \\ Seiichi Manyama, Feb 12 2022
CROSSREFS
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), A351310 (k=5), A351311 (k=6), A351313 (k=7), A351314 (k=8), A351315 (k=9), this sequence (k=10).
Cf. A010052.
Sequence in context: A017446 A017578 A370255 * A017703 A013968 A036098
KEYWORD
nonn,easy,mult
AUTHOR
Wesley Ivan Hurt, Feb 06 2022
STATUS
approved