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A062401 a(n) = phi(sigma(n)).

%I A062401 #35 Jun 06 2024 06:20:33
%S A062401 1,2,2,6,2,4,4,8,12,6,4,12,6,8,8,30,6,24,8,12,16,12,8,16,30,12,16,24,
%T A062401 8,24,16,36,16,18,16,72,18,16,24,24,12,32,20,24,24,24,16,60,36,60,24,
%U A062401 42,18,32,24,32,32,24,16,48,30,32,48,126,24,48,32,36,32,48,24,96,36,36,60
%N A062401 a(n) = phi(sigma(n)).
%D A062401 D. S. Mitrinovic et al., Handbook of Number Theory, Kluwer, p. 14.
%H A062401 T. D. Noe, <a href="/A062401/b062401.txt">Table of n, a(n) for n = 1..10000</a>
%F A062401 sigma(a(n)) = A062402(sigma(n)) or phi(A062402(n)) = a(phi(n)). - _Labos Elemer_, Jul 22 2004
%e A062401 a(9) = 12 because sigma(9) = 13 and phi(13) = 12.
%p A062401 with(numtheory); A062401:=n->phi(sigma(n)); seq(A062401(n), n=1..50); # _Wesley Ivan Hurt_, Apr 07 2014
%t A062401 Table[EulerPhi[DivisorSigma[1, n]], {n, 1, 80}] (* _Carl Najafi_, Aug 16 2011 *)
%o A062401 (PARI) vector(150, n, eulerphi(sigma(n)))
%o A062401 (PARI) for (n=1, 10000, write("b062401.txt", n, " ", eulerphi(sigma(n))) ) \\ _Harry J. Smith_, Aug 07 2009
%o A062401 (Haskell)
%o A062401 a062401 = a000010 . a000203  -- _Reinhard Zumkeller_, Jan 04 2013
%Y A062401 Cf. A000203, A000010, A062402, A096852, A096857, A096994, A096995, A033632.
%Y A062401 Cf. A001229 (fixed points).
%K A062401 nonn
%O A062401 1,2
%A A062401 _Jason Earls_, Jul 08 2001