cp's OEIS Frontend

A332825 a(n) = A019565(phi(n)).

%I A332825 #9 Feb 25 2020 18:34:02
%S A332825 2,2,3,3,5,3,15,5,15,5,21,5,35,15,7,7,11,15,33,7,35,21,165,7,55,35,33,
%T A332825 35,385,7,1155,11,55,11,77,35,65,33,77,11,91,35,273,55,77,165,1365,11,
%U A332825 273,55,13,77,715,33,91,77,65,385,3003,11,5005,1155,65,13,143,55,51,13,455,77,255,77,119,65,91,65,5005,77
%N A332825 a(n) = A019565(phi(n)).
%H A332825 Antti Karttunen, <a href="/A332825/b332825.txt">Table of n, a(n) for n = 1..8192</a>
%F A332825 a(n) = A019565(A000010(n)).
%F A332825 a(n) = A332824(n) / A318834(n)
%F A332825 a(4n) = A003961(a(2n)), a(4n+2) = a(2n+1).
%o A332825 (PARI)
%o A332825 A019565(n) = {my(j,v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ From A019565
%o A332825 A332825(n) = A019565(eulerphi(n));
%Y A332825 Cf. A000010, A003961, A019565, A318834, A332824.
%K A332825 nonn
%O A332825 1,1
%A A332825 _Antti Karttunen_, Feb 25 2020