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%I #17 Sep 08 2022 08:46:23
%S 1,2,5,19,7,25,9,39,16,61,13,101,15,113,469,2501,19,2809,21,11263,865,
%T 265,25,133489,178,365,1300,29431,31,327601,33,40019,2017,613,2069,
%U 3659761,39,761,2773,921041,43,1203049,45,109255,66692,1105,49,410700293,444
%N a(n) = numerator of Sum_{d|n} tau(d)/pod(d) where tau(k) = the number of the divisors of k (A000005) and pod(k) = the product of the divisors of k (A007955).
%C Sum_{d|n} tau(d)/pod(d) > 1 for all n > 1.
%F a(p) = p + 2 for prime p > 2.
%e For n=4; Sum_{d|4} tau(d)/pod(d) = tau(1)/pod(1) + tau(2)/pod(2) + tau(4)/pod(4) = 1/1 + 2/2 + 3/8 = 19/8; a(4) = 19.
%o (Magma) [Numerator(&+[NumberOfDivisors(d) / &*[c: c in Divisors(d)]: d in Divisors(n)]): n in [1..100]]
%o (PARI) a(n) = numerator(sumdiv(n, d, numdiv(d)/vecprod(divisors(d)))); \\ _Michel Marcus_, Jan 25 2019
%Y Cf. A000005, A007955, A323707 (denominator).
%K nonn,frac
%O 1,2
%A _Jaroslav Krizek_, Jan 24 2019
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