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 A035220 Coefficients in expansion of Dirichlet series Product_p (1-(Kronecker(m,p)+1)*p^(-s)+Kronecker(m,p)*p^(-2s))^(-1) for m = 38. 2
 1, 1, 0, 1, 0, 0, 0, 1, 1, 0, 2, 0, 2, 0, 0, 1, 2, 1, 1, 0, 0, 2, 0, 0, 1, 2, 0, 0, 2, 0, 2, 1, 0, 2, 0, 1, 2, 1, 0, 0, 0, 0, 2, 2, 0, 0, 0, 0, 1, 1, 0, 2, 2, 0, 0, 0, 0, 2, 0, 0, 0, 2, 0, 1, 0, 0, 0, 2, 0, 0, 2, 1, 2, 2, 0, 1, 0, 0, 2, 0, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,11 LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 FORMULA From Amiram Eldar, Nov 20 2023: (Start) a(n) = Sum_{d|n} Kronecker(38, d). Multiplicative with a(p^e) = 1 if Kronecker(38, p) = 0 (p = 2 or 19), a(p^e) = (1+(-1)^e)/2 if Kronecker(38, p) = -1 (p is in A038916), and a(p^e) = e+1 if Kronecker(38, p) = 1 (p is in A038915 \ {2, 19}). Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k) = log(6*sqrt(38)+37)/sqrt(38) = 0.698181923868... . (End) MATHEMATICA a[n_] := DivisorSum[n, KroneckerSymbol[38, #] &]; Array[a, 100] (* Amiram Eldar, Nov 20 2023 *) PROG (PARI) my(m = 38); direuler(p=2, 101, 1/(1-(kronecker(m, p)*(X-X^2))-X)) (PARI) a(n) = sumdiv(n, d, kronecker(38, d)); \\ Amiram Eldar, Nov 20 2023 CROSSREFS Cf. A038915, A038916. Sequence in context: A091395 A248107 A352561 * A227618 A366533 A340683 Adjacent sequences: A035217 A035218 A035219 * A035221 A035222 A035223 KEYWORD nonn,easy,mult AUTHOR N. J. A. Sloane STATUS approved

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Last modified September 19 09:17 EDT 2024. Contains 376007 sequences. (Running on oeis4.)