OFFSET
1,1
COMMENTS
Numbers such that at least one of the exponents in their prime factorization is of the form 4*m + 3.
The asymptotic density of this sequence is 1 - zeta(4)/zeta(3) = 0.0996073223... (Cohen, 1963).
The number of divisors of all the terms is divisible by 4.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
Eckford Cohen, Arithmetical Notes, XIII. A Sequal to Note IV, Elemente der Mathematik, Vol. 18 (1963), pp. 8-11.
EXAMPLE
8 is a term since 8 = 2^3 and 3 is of the form 4*m + 3.
MATHEMATICA
Select[Range[540], Max[Mod[FactorInteger[#][[;; , 2]], 4]] == 3 &]
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Jul 26 2020
STATUS
approved