This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A163377 #8 Dec 21 2016 02:43:06 %S A163377 1,1,1,2,1,2,1,2,2,2,1,2,1,2,2,3,1,2,1,2,2,2,1,3,2,2,2,2,1,3,1,2,2,2, %T A163377 2,4,1,2,2,3,1,3,1,2,2,2,1,3,2,2,2,2,1,3,2,3,2,2,1,3,1,2,2,4,2,3,1,2, %U A163377 2,3,1,3,1,2,2,2,2,3,1,3,3,2,1,3,2,2,2,3,1,3,2,2,2,2,2,3 %N A163377 a(n) = tau(phi(tau(n))). %H A163377 G. C. Greubel, <a href="/A163377/b163377.txt">Table of n, a(n) for n = 1..1000</a> %F A163377 a(n) = A000005(A000010(A000005(n))) = A000005(A163109(n)) = A062821(A000005(n)). %t A163377 DivisorSigma[0, EulerPhi[DivisorSigma[0, Range[100]]]] (* _G. C. Greubel_, Dec 20 2016 *) %o A163377 (PARI) vector(100, n, numdiv(eulerphi(numdiv(n)))) \\ _G. C. Greubel_, Dec 20 2016 %Y A163377 Cf. A000005, A000010, A062821, A163109. %K A163377 nonn %O A163377 1,4 %A A163377 _Jaroslav Krizek_, Jul 25 2009