A328226 Primitive elements of A278638.

6, 15, 20, 21, 28, 33, 35, 44, 52, 55, 65, 68, 76, 77, 85, 91, 95, 115, 117, 119, 133, 143, 145, 153, 155, 161, 171, 184, 185, 187, 203, 205, 207, 209, 215, 217, 221, 232, 235, 247, 248, 253, 259, 261, 265, 279, 287, 296, 299, 301, 305, 319, 323, 328, 329, 333, 335, 341

Offset: 1

Author

Max Alekseyev, Oct 08 2019

Keywords

• nonn

Comments

A number k belongs to this sequence if k is a term of A278638, while its proper divisors are not. It follows that A278638 is formed by the multiples of the terms of this sequence.

Crossrefs

Cf. A000961, A001284, A072207, A278638.