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 A279507 #8 Sep 08 2022 08:46:18
%S A279507 1,0,1,0,2,0,3,1,2,1,5,0,6,1,2,1,8,1,9,1,3,2,11,1,6,3,4,2,14,1,15,2,5,
%T A279507 4,6,1,18,4,6,2,20,1,21,3,4,5,23,1,14,3,8,4,26,2,10,3,9,7,29,1,30,7,6,
%U A279507 4,12,2,33,5,11,3,35,2,36,9,6,6,15,3,39,3
%N A279507 a(n) = floor(phi(n)/tau(n)).
%C A279507 a(n) = floor(A000010(n)/A000005(n)).
%C A279507 There are 11 numbers n such that phi(n) <= tau(n) and 7 numbers n such that phi(n) = tau(n); see A020490 and A020488.
%C A279507 Sequences b(k) of numbers n such that a(n) = k are finite for all k >=0; see A279508 (the smallest numbers n such that a(n) = k for k>=0) and A279509 (the largest numbers n such that a(n) = k for k>=0).
%C A279507 See A140475 (numbers n such that floor(phi(n)/tau(n)) > floor(phi(m)/tau(m)) for all m < n).
%H A279507 Jaroslav Krizek, <a href="/A279507/b279507.txt">Table of n, a(n) for n = 1..2000</a>
%F A279507 a(n) > 1 for numbers in A279289.
%e A279507 For n=5; a(5) = floor(phi(5)/tau(5)) = floor(4/2) = 2.
%t A279507 Table[Floor[EulerPhi[n]/DivisorSigma[0, n]], {n,1,25}] (* _G. C. Greubel_, Dec 13 2016 *)
%o A279507 (Magma) [Floor(EulerPhi(n)/NumberOfDivisors(n)): n in[1..100]]
%o A279507 (PARI) for(n=1, 25, print1(floor(eulerphi(n)/numdiv(n)), ", ")) \\ _G. C. Greubel_, Dec 13 2016
%Y A279507 Cf. A000005, A000010, A020488, A020490, A140475, A279289, A279508, A279509.
%K A279507 nonn
%O A279507 1,5
%A A279507 _Jaroslav Krizek_, Dec 13 2016