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%I #21 Jan 04 2024 17:39:57
%S 1,2,4,6,8,12,18,24,30,36,48,60,72,84,90,120,144,180,240,252,360,420,
%T 480,504,540,720,840,900,1008,1080,1260,1440,1680,1800,2520,2640,2880,
%U 3360,3780,3960,5040,5280,5400,5460,5544,6300,7560,7920,8400,10080,10920,12600,15120,15840,16380,18480
%N Numbers k such that d(k)/k >= d(m)/m for all m > k, where d(k) is the number-of-divisors function A000005(k).
%C Because of the bound d(m) <= 2*sqrt(m), in order for k to be in the sequence it suffices that d(k)/k >= d(m)/m for k < m < (2*k/d(k))^2. - _Robert Israel_, Jan 23 2023
%D David desJardins, Posting to Math Fun Mailing List, Jun 21 2022.
%p N:= 10^6:
%p Q:= [seq(numtheory:-tau(k)/k, k=1..N)]:
%p V:= Vector(10^6):
%p r:= 2/10^3:
%p for n from 10^6 to 1 by -1 do
%p r:= max(Q[n],r);
%p V[n]:= r;
%p od:
%p select(i -> Q[i] >= V[i+1], [$1..10^6-1]); # _Robert Israel_, Jan 23 2023
%Y Cf. A000005, A066523, A354769, A368523.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Jun 21 2022
%E More terms from _Robert Israel_, Jan 23 2023
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