OFFSET
1,1
COMMENTS
All terms are divisible by 4.
A092259 (numbers congruent to {4,8} (mod 12)) is a subset.
Sequence also includes all numbers of the form 48*k where k is congruent to {1,2} (mod 3) (A001651).
Additional entries of the form 48k, where k is divisible by three have k values of 12*{1,2,4,5,7,8,10,11,12,13,14,16,17,19,20,22,23,24,...}
From Robert Israel, Jan 29 2019: (Start)
Sequence is closed under multiplication. (End)
The asymptotic density of this sequence is 2/11. - Amiram Eldar, Mar 25 2021
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
EXAMPLE
tau(4*20) = 10, tau(3*20)=12. So 20 is in the sequence.
MAPLE
with(numtheory): for n from 1 to 300 do if tau(4*n) < tau(3*n) then print(n) fi od
MATHEMATICA
Select[Range[4, 240, 4], #1 < #2 & @@ DivisorSigma[0, # {4, 3}] &] (* Michael De Vlieger, Jan 29 2019 *)
Select[Range[240], IntegerExponent[#, 2] - 2 * IntegerExponent[#, 3] >= 2 &] (* Amiram Eldar, Mar 25 2021 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Gary Detlefs, Jan 28 2019
STATUS
approved