A261417 Numbers n such that both ceiling(sqrt(n)) and ceiling(n^(1/3)) divide n.

1, 2, 4, 6, 9, 12, 36, 56, 64, 90, 100, 110, 132, 144, 156, 210, 400, 576, 702, 729, 870, 900, 930, 1056, 1089, 1122, 1332, 1560, 2352, 2450, 2970, 3600, 4032, 4096, 4556, 4624, 4692, 5112, 5184, 5256, 5852, 7140, 8190, 9702, 9900, 12432, 14400, 15500, 15625, 16770, 16900, 17030, 18090, 18225, 18360, 19740

Offset: 1

Author

N. J. A. Sloane, Aug 26 2015

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..229

Crossrefs

Intersection of A002620 and A261011. Contains A261206 as a subsequence.

Programs

Magma

[n: n in [1..2000] | n mod Ceiling((n^(1/2))) eq 0 and n mod Ceiling((n^(1/3))) eq 0 ];

Mathematica

Select[Range[200000], Mod[#, Ceiling[#^(1/2)]] == Mod[#, Ceiling[#^(1/3)]] == 0 &] (* Vincenzo Librandi, Aug 21 2016 *)

PARI

is(n) = Mod(n, ceil(sqrt(n)))==0 && Mod(n, ceil(n^(1/3)))==0 \\ Felix Fröhlich, Aug 21 2016