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A289624 a(n) = A002322(n)/A007947(A034380(n)).

%I A289624 #21 Mar 07 2020 14:57:16
%S A289624 1,1,2,2,4,2,6,1,6,4,10,1,12,6,2,2,16,6,18,2,3,10,22,1,20,12,18,3,28,
%T A289624 2,30,4,5,16,6,3,36,18,6,2,40,3,42,5,6,22,46,2,42,20,8,6,52,18,10,3,9,
%U A289624 28,58,2,60,30,1,8,6,5,66,8,11,6,70,3,72,36,10,9,15,6,78,2,54,40,82,3,8,42,14,5,88,6,2,11,15,46
%N A289624 a(n) = A002322(n)/A007947(A034380(n)).
%H A289624 Antti Karttunen, <a href="/A289624/b289624.txt">Table of n, a(n) for n = 1..65536</a>
%F A289624 a(n) = A002322(n) / A007947(A034380(n)) = A002322(n) / A007947(A000010(n) / A002322(n)).
%p A289624 with(numtheory):
%p A289624 rad := n -> ilcm(op(factorset(n))):
%p A289624 a := n -> lambda(n)/rad(phi(n)/lambda(n)):
%p A289624 seq(a(n), n=1..94); # _Peter Luschny_, Jul 17 2017
%t A289624 a007947[n_]:=Last@ Select[Divisors[n], SquareFreeQ[#] &]; Table[Numerator[CarmichaelLambda[n]/a007947[EulerPhi[n]/CarmichaelLambda[n]]], {n, 100}] (* _Indranil Ghosh_, Jul 17 2017 *)
%o A289624 (PARI)
%o A289624 A002322(n) = lcm(znstar(n)[2]); \\ This function from _Charles R Greathouse IV_, Aug 04 2012
%o A289624 A007947(n) = factorback(factorint(n)[, 1]); \\ This function from _Andrew Lelechenko_, May 09 2014
%o A289624 A289624(n) = A002322(n)/A007947(eulerphi(n)/A002322(n));
%o A289624 (Sage)
%o A289624 from sage.crypto.util import carmichael_lambda
%o A289624 def A007947(n): return mul(p for p in prime_divisors(n))
%o A289624 def A000010(n): return euler_phi(n)
%o A289624 def A002322(n): return carmichael_lambda(n)
%o A289624 def A289624(n): return A002322(n)/A007947(A000010(n)/A002322(n))
%o A289624 print([A289624(n) for n in (1..94)]) # _Peter Luschny_, Jul 17 2017
%Y A289624 Cf. A000010, A002322, A007947, A034380, A080400.
%K A289624 nonn
%O A289624 1,3
%A A289624 _Antti Karttunen_, Jul 17 2017