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%I #13 Sep 08 2022 08:46:24
%S 1,5,7,27,11,25,15,231,76,97,23,2185,27,369,91,3727,35,9049,39,19041,
%T 1565,887,47,48775,306,615,2092,65,59,63601,63,119327,1259,1042,4143,
%U 55891387,75,2595,5243,1278633,83,713689,87,96711,125216,3785,95,339061279
%N a(n) = numerator of Sum_{d|n} sigma(d)/pod(d) where sigma(k) = the sum of the divisors of k (A000203) and pod(k) = the product of the divisors of k (A007955).
%C Sum_{d|n} sigma(d)/pod(d) > 1 for all n > 1.
%F a(p) = 2p+1 for p = primes (A000040).
%e For n=4; Sum_{d|4} sigma(d)/pod(d) = sigma(1)/pod(1) + sigma(2)/pod(2) + sigma(4)/pod(4) = 1/1 + 3/2 + 7/8 = 27/8; a(4) = 27.
%t Array[Numerator@ DivisorSum[#, Total[#]/(Times @@ #) &@ Divisors@ # &] &, 48] (* _Michael De Vlieger_, Feb 24 2019 *)
%o (Magma) [Numerator(&+[SumOfDivisors(d) / &*[c: c in Divisors(d)]: d in Divisors(n)]): n in [1..100]]
%o (PARI) a(n) = numerator(sumdiv(n, d, sigma(d)/vecprod(divisors(d)))); \\ _Michel Marcus_, Feb 23 2019
%Y Cf. A000040, A000203, A007955, A324364 (denominators).
%K nonn,frac
%O 1,2
%A _Jaroslav Krizek_, Feb 23 2019
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