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A151948 a(n) = tau(sigma(phi(n))). 1

%I

%S 1,1,2,2,2,2,6,2,6,2,6,2,6,6,4,4,2,6,4,4,6,6,9,4,8,6,4,6,8,4,12,2,8,2,

%T 12,6,4,4,12,2,12,6,12,8,12,9,12,2,12,8,6,12,6,4,12,12,4,8,12,2,16,12,

%U 4,6,6,8,15,6,12,12,15,12,8,4,12,4,16,12,16

%N a(n) = tau(sigma(phi(n))).

%H Antti Karttunen, <a href="/A151948/b151948.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A000005(A000203(A000010(n))) = A000005(A062402(n)) = A062068(A000010(n)).

%o (PARI) A151948(n) = numdiv(sigma(eulerphi(n))); \\ _Antti Karttunen_, Aug 22 2017

%Y Cf. A000005, A000010, A000203, A062068, A062402, A163375.

%K nonn

%O 1,3

%A _Jaroslav Krizek_, Jul 20 2009

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Last modified November 22 10:59 EST 2019. Contains 329389 sequences. (Running on oeis4.)