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A336476 a(n) = gcd(A000593(n), A336475(n)). 4

%I #9 Jul 30 2020 20:20:20

%S 1,1,2,1,2,2,2,1,1,2,2,2,2,2,12,1,2,1,2,2,4,2,2,2,1,2,4,2,2,12,2,1,12,

%T 2,4,1,2,2,4,2,2,4,2,2,6,2,2,2,3,1,12,2,2,4,4,2,4,2,2,12,2,2,2,1,4,12,

%U 2,2,12,4,2,1,2,2,2,2,4,4,2,2,1,2,2,4,4,2,12,2,2,6,28,2,4,2,20,2,2,3,6,1,2,12,2,2,24

%N a(n) = gcd(A000593(n), A336475(n)).

%C All odd terms k in A001599 (Ore's Harmonic numbers) satisfy a(k) = A336475(k).

%H Antti Karttunen, <a href="/A336476/b336476.txt">Table of n, a(n) for n = 1..16384</a>

%H Antti Karttunen, <a href="/A336476/a336476.txt">Data supplement: n, a(n) computed for n = 1..65537</a>

%F a(n) = gcd(A000593(n), A336475(n)).

%F a(n) = A324121(A000265(n)).

%o (PARI)

%o A000593(n) = sigma(n>>valuation(n, 2));

%o A336475(n) = { my(f=factor(n)); prod(i=1, #f~, if(2==f[i,1],1,(1+f[i,2]) * (f[i,1]^f[i,2]))); };

%o A336476(n) = gcd(A000593(n), A336475(n));

%Y Cf. A000265, A000593, A001227, A001599, A324121, A336475.

%Y Cf. also A324058, A336320.

%K nonn

%O 1,3

%A _Antti Karttunen_, Jul 30 2020

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Last modified August 11 12:11 EDT 2024. Contains 375069 sequences. (Running on oeis4.)