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A318836 Product_{d|n, dA007431(d) > 0} prime(A007431(d)), where A007431 is the Möbius transform of Euler's totient function.

%I A318836 #16 Jul 27 2024 19:14:19
%S A318836 1,2,2,2,2,4,2,4,4,10,2,8,2,22,20,12,2,28,2,20,44,46,2,48,10,62,28,44,
%T A318836 2,100,2,84,92,94,110,112,2,118,124,300,2,484,2,92,700,146,2,1008,22,
%U A318836 530,188,124,2,1036,230,1452,236,206,2,2000,2,218,3388,1596,310,2116,2,188,292,5170,2,7056,2,298,5300,236,506
%N A318836 Product_{d|n, d<n, A007431(d) > 0} prime(A007431(d)), where A007431 is the Möbius transform of Euler's totient function.
%H A318836 Antti Karttunen, <a href="/A318836/b318836.txt">Table of n, a(n) for n = 1..4096</a>
%F A318836 a(n) = product_{d|n, d<n} A008578(1+A007431(d)).
%F A318836 For all n >= 1, A056239(a(n)) = A062790(n).
%o A318836 (PARI)
%o A318836 A007431(n) = sumdiv(n,d,moebius(n/d)*eulerphi(d));
%o A318836 A318836(n) = { my(m=1); fordiv(n,d,if((d<n)&&(A007431(d)!=0),m *= prime(A007431(d)))); (m); };
%Y A318836 Cf. A007431, A062790, A318837 (rgs-transform).
%Y A318836 Cf. also A318838.
%K A318836 nonn
%O A318836 1,2
%A A318836 _Antti Karttunen_, Sep 05 2018