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a(n) = Product_{d|n, d>1} prime(1+(d mod 4)).
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%I #12 Feb 28 2024 10:49:48

%S 1,5,7,10,3,175,7,20,21,75,7,700,3,175,147,40,3,2625,7,300,147,175,7,

%T 2800,9,75,147,700,3,91875,7,80,147,75,147,21000,3,175,147,1200,3,

%U 91875,7,700,1323,175,7,11200,21,1125,147,300,3,91875,147,2800,147,75,7,1470000,3,175,3087,160,27,91875,7,300,147,91875,7,168000,3,75

%N a(n) = Product_{d|n, d>1} prime(1+(d mod 4)).

%H Antti Karttunen, <a href="/A320114/b320114.txt">Table of n, a(n) for n = 1..8192</a>

%F a(n) = Product_{d|n, d>1} prime(1+(d mod 4)).

%o (PARI) A320114(n) = { my(m=1); fordiv(n,d,if(d>1, m *= prime(1+(d%4)))); (m); };

%Y Cf. A320115 (rgs-transform), A320116.

%Y Cf. also A319984.

%Y Cf. A002144 (a(n)=3), A002145 (a(n)=7).

%K nonn

%O 1,2

%A _Antti Karttunen_, Oct 06 2018