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A340366 a(n) = A324106(n) / gcd(A005940(n), A324106(n)), where A324106(n) is multiplicative with a(p^e) = A005940(p^e). 4

%I #5 Jan 06 2021 17:48:50

%S 1,1,1,1,1,1,1,1,1,1,1,1,1,1,5,1,1,1,1,1,27,1,1,1,1,1,1,1,1,5,1,1,45,

%T 1,15,1,1,1,25,1,1,27,1,1,1,1,1,1,1,1,11,1,1,1,1,1,9,1,1,5,1,1,7,1,

%U 125,45,1,1,27,15,1,1,1,1,49,1,27,25,1,1,1,1,1,27,1,1,25,1,1,1,3,1,243,1,7,1,1,1,35,1,1,11

%N a(n) = A324106(n) / gcd(A005940(n), A324106(n)), where A324106(n) is multiplicative with a(p^e) = A005940(p^e).

%H Antti Karttunen, <a href="/A340366/b340366.txt">Table of n, a(n) for n = 1..16384</a>

%F a(n) = A324106(n) / A340364(n) = A324106(n) / gcd(A005940(n), A324106(n)).

%o (PARI)

%o A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t };

%o A324106(n) = { my(f=factor(n)); prod(i=1, #f~, A005940(f[i,1]^f[i,2])); };

%o A340366(n) = { my(u=A324106(n)); (u / gcd(u, A005940(n))); };

%Y Cf. A005940, A324106, A340364, A340365.

%K nonn

%O 1,15

%A _Antti Karttunen_, Jan 06 2021

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Last modified April 25 01:35 EDT 2024. Contains 371964 sequences. (Running on oeis4.)