A121683 Untouchable cubes.

216, 1728, 5832, 8000, 13824, 21952, 27000, 74088, 110592, 157464, 175616, 195112, 216000, 238328, 287496, 314432, 343000, 373248, 729000, 884736, 941192, 1061208, 1124864, 1259712, 1481544, 1728000, 2000376, 2097152, 2628072, 2744000, 2985984, 3241792, 3511808

Offset

1,1

Comments

Untouchable numbers (cf. A005114) that are third powers (cf. A000578); a(1) to a(7) are the third powers of 6, 12, 18, 20, 24, 28, 30.

Links

Amiram Eldar, Table of n, a(n) for n = 1..45

Example

216 = 6^3 = A000578(6) = A005114(13).

Crossrefs

Intersection of A000578 and A005114.

Cf. A111278 (untouchable squares).

Sequence in context: A233974 A016863 A033698 * A016911 A370693 A323801

Adjacent sequences: A121680 A121681 A121682 * A121684 A121685 A121686

Keyword

nonn

Author

Klaus Brockhaus, Aug 15 2006

Extensions

a(8)-a(30) from Donovan Johnson, Jul 19 2008

Terms a(26)-a(30) corrected and a(31)-a(33) added by Amiram Eldar, Sep 23 2022

Status

approved