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%I #12 May 13 2022 18:24:37
%S 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,1,1,2,1,
%T 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,4,1,1,1,
%U 2,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,3,1,2,1,1,1,1,1,1,1,1,1,1,1,2
%N a(n) = A049559(n) / A187730(n), where A049559(n) and A187730(n) are the greatest common divisors between Euler phi(n) and n-1, and between Carmichael lambda(n) and n-1, respectively.
%H Antti Karttunen, <a href="/A353801/b353801.txt">Table of n, a(n) for n = 1..100000</a>
%t a[n_] := GCD[n - 1, EulerPhi[n]] / GCD[n - 1, CarmichaelLambda[n]]; Array[a, 100] (* _Amiram Eldar_, May 13 2022 *)
%o (PARI)
%o A049559(n) = gcd(n-1, eulerphi(n));
%o A187730(n) = gcd(lcm(znstar(n)[2]), n-1); \\ From A187730
%o A353801(n) = (A049559(n) / A187730(n));
%Y Cf. A280262 (positions of terms > 1).
%Y Cf. A000010, A002322, A049559, A187730, A353483, A353808.
%Y Cf. also A034380.
%K nonn
%O 1,21
%A _Antti Karttunen_, May 13 2022