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%I #18 Nov 18 2023 06:28:19
%S 1,2,0,3,0,0,0,4,1,0,0,0,2,0,0,5,1,2,2,0,0,0,0,0,1,4,0,0,0,0,0,6,0,2,
%T 0,3,0,4,0,0,0,0,2,0,0,0,2,0,1,2,0,6,2,0,0,0,0,0,2,0,0,0,0,7,0,0,2,3,
%U 0,0,0,4,0,0,0,6,0,0,0,0,1
%N Coefficients in expansion of Dirichlet series Product_p (1-(Kronecker(m,p)+1)*p^(-s)+Kronecker(m,p)*p^(-2s))^(-1) for m = 17.
%C Coefficients of Dedekind zeta function for the quadratic number field of discriminant 17. See A002324 for formula and Maple code. - _N. J. A. Sloane_, Mar 22 2022
%H G. C. Greubel, <a href="/A035199/b035199.txt">Table of n, a(n) for n = 1..10000</a>
%F Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k) = 2*log(4+sqrt(17))/sqrt(17) = 1.016084... . - _Amiram Eldar_, Oct 11 2022
%F From _Amiram Eldar_, Nov 18 2023: (Start)
%F a(n) = Sum_{d|n} Kronecker(17, d).
%F Multiplicative with a(17^e) = 1, a(p^e) = (1+(-1)^e)/2 if Kronecker(17, p) = -1 (p is in A038890), and a(p^e) = e+1 if Kronecker(17, p) = 1 (p is in A038889 \ {17}). (End)
%t a[n_] := If[n < 0, 0, DivisorSum[n, KroneckerSymbol[17, #] &]]; Table[ a[n], {n, 1, 100}] (* _G. C. Greubel_, Apr 27 2018 *)
%o (PARI) my(m=17); direuler(p=2,101,1/(1-(kronecker(m,p)*(X-X^2))-X))
%o (PARI) a(n) = sumdiv(n, d, kronecker(17, d)); \\ _Amiram Eldar_, Nov 18 2023
%Y Dedekind zeta functions for imaginary quadratic number fields of discriminants -3, -4, -7, -8, -11, -15, -19, -20 are A002324, A002654, A035182, A002325, A035179, A035175, A035171, A035170, respectively.
%Y Dedekind zeta functions for real quadratic number fields of discriminants 5, 8, 12, 13, 17, 21, 24, 28, 29, 33, 37, 40 are A035187, A035185, A035194, A035195, A035199, A035203, A035188, A035210, A035211, A035215, A035219, A035192, respectively.
%Y Cf. A038889, A038890.
%K nonn,easy,mult
%O 1,2
%A _N. J. A. Sloane_
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