A048168 n is divisible by the square of the number of unitary divisors of n (A034444).

1, 4, 8, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, 176, 192, 208, 224, 256, 272, 288, 304, 320, 352, 368, 384, 400, 416, 432, 448, 464, 496, 512, 544, 576, 592, 608, 640, 656, 688, 704, 736, 752, 768, 784, 800, 832, 848, 864, 896, 928, 944, 960, 976, 992

Offset

1,2

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Example

x=2032=16*127 has 4 unitary divisors: {1,16,127,2032} and ud[ x ]^2=16 divides 2032.

Mathematica

Select[Range[10^3], Divisible[#, 4^PrimeNu[#]] &] (* Amiram Eldar, Aug 05 2019 *)

Crossrefs

A034444, A046754, A048166.

Sequence in context: A217313 A101434 A293780 * A175341 A317705 A318692

Adjacent sequences: A048165 A048166 A048167 * A048169 A048170 A048171

Keyword

nonn

Author

Labos Elemer

Status

approved