A088069 Cubes sandwiched between two numbers divisible by cubes > 1.

4913, 6859, 166375, 704969, 2048383, 4173281, 7880599, 12649337, 15438249, 15813251, 19902511, 28372625, 34328125, 40353607, 53582633, 71473375, 90518849, 115501303, 141420761, 174676879, 208527857, 251239591, 294079625

Offset

1,1

Comments

Sequence is infinite. If k is a member then so is k^3. Subsidiary sequence: fourth powers sandwiched between two numbers divisible by fourth powers.

Links

Table of n, a(n) for n=1..23.

Example

4913 = 17^3 is a term since 4912 is divisible by 8 and 4914 is divisible by 27.

Mathematica

Select[Range[2, 1000], Last[Union[Transpose[FactorInteger[ #^3 - 1]][[2]]]] > 2 && Last[Union[Transpose[FactorInteger[ #^3 + 1]][[2]]]] > 2 &]^3 (* Tanya Khovanova, Sep 08 2007 *)

Crossrefs

Subsequence of A088035.

Cf. A088068.

Sequence in context: A250908 A179144 A036530 * A283034 A114770 A013807

Adjacent sequences: A088066 A088067 A088068 * A088070 A088071 A088072

Keyword

nonn

Author

Amarnath Murthy, Sep 22 2003

Extensions

Corrected and extended by Ray Chandler, Sep 27 2003

Offset changed by Andrew Howroyd, Sep 22 2024

Status

approved