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A336593
Numbers k such that k/A008835(k) is cubeful (A036966), where A008835(k) is the largest 4th power dividing k.
3
8, 24, 27, 40, 54, 56, 72, 88, 104, 108, 120, 125, 128, 135, 136, 152, 168, 184, 189, 200, 216, 232, 248, 250, 264, 270, 280, 296, 297, 312, 328, 343, 344, 351, 360, 375, 376, 378, 384, 392, 408, 424, 432, 440, 456, 459, 472, 488, 500, 504, 513, 520, 536, 540
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
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
Complement of A336592.
Complement of A336594 within A252849.
A176297 is a subsequence.
Sequence in context: A374459 A195086 A366761 * A176297 A375072 A175496
KEYWORD
nonn
AUTHOR
Amiram Eldar, Jul 26 2020
STATUS
approved