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%I #10 Oct 04 2019 23:30:14
%S 1,1,1,2,1,2,1,2,3,2,1,2,1,2,1,4,1,6,1,4,3,2,1,2,5,2,9,2,1,2,1,8,1,2,
%T 1,6,1,2,3,4,1,6,1,2,3,2,1,4,7,10,1,4,1,18,5,2,3,2,1,4,1,2,3,16,1,2,1,
%U 4,1,2,1,6,1,2,5,2,1,6,1,4,27,2,1,6,1,2,1,2,1,6,1,2,3,2,1,8,1,14,3,20,1,2,1,4,3
%N a(n) = gcd(n, A002322(n)), where A002322 is Carmichael lambda, also known as psi.
%H Antti Karttunen, <a href="/A327979/b327979.txt">Table of n, a(n) for n = 1..65537</a>
%F a(n) = gcd(n, A002322(n)).
%t Array[GCD[#, CarmichaelLambda[#]] &, 100] (* _Amiram Eldar_, Oct 04 2019 *)
%o (PARI) A327979(n) = gcd(n, lcm(znstar(n)[2]));
%Y Cf. A002322.
%Y Cf. also A009191, A009194, A009195, A306695.
%K nonn
%O 1,4
%A _Antti Karttunen_, Oct 04 2019