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A340364 a(n) = gcd(A005940(n), A324106(n)), where A324106(n) is multiplicative with a(p^e) = A005940(p^e).

%I A340364 #6 Jan 06 2021 17:48:36
%S A340364 1,2,3,4,5,6,9,8,7,10,15,12,25,18,3,16,11,14,21,20,1,30,45,24,49,50,
%T A340364 75,36,125,6,81,32,1,22,3,28,55,42,3,40,77,2,105,60,35,90,135,48,121,
%U A340364 98,3,100,245,150,75,72,7,250,375,12,625,162,9,64,1,2,39,44,5,6,99,56,91,110,3,84,5,6,189,80,143,154,231
%N A340364 a(n) = gcd(A005940(n), A324106(n)), where A324106(n) is multiplicative with a(p^e) = A005940(p^e).
%H A340364 Antti Karttunen, <a href="/A340364/b340364.txt">Table of n, a(n) for n = 1..16384</a>
%F A340364 a(n) = gcd(A005940(n), A324106(n)) = gcd(A005940(n), A340362(n)).
%o A340364 (PARI)
%o A340364 A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t }; \\ From A005940
%o A340364 A324106(n) = { my(f=factor(n)); prod(i=1, #f~, A005940(f[i,1]^f[i,2])); };
%o A340364 A340364(n) = gcd(A005940(n), A324106(n));
%Y A340364 Cf. A005940, A324106, A340362, A340365, A340366.
%Y A340364 Cf. also A339969.
%K A340364 nonn
%O A340364 1,2
%A A340364 _Antti Karttunen_, Jan 06 2021